US2411633A - Abrasive reamer - Google Patents

Description

yNOV- 26, 1946- A. oBERHoLTZ, JR 2,411,533

` ABRASIVE BEAMER Filed Dec. 21, 1942 76 ToR JNVEN ANTHo Y oBERHo rz,./R.

AT TORNE Y.

Patented Nov. 26, 1946 UNITED STATES PATENT OFFICE 2,411,633 ABl'tAslvE BEAMER Anthony Oberholtz, Jr., Los Angeles, Calif. Application December 21, 1942, Serial No. 469,590

IZ Claims. (Cl. 51-1843) 1 This invention relates to improvements in abrasive reamers of the type illustrated in United States. Letters Patents 1,841,343, 1,910,658 and 1,910,659; although the teachings of the present invention may be employed with equal advantage in connection with other types of honing andreaming devices. 'o

It contemplates more especially the provision of improved means for increasing the range of bore sizes that may be honed. or reamed, and more particularly enables muchL smaller bores to be honed Without sacrificing the large range of bores with the same tool serving the entire range. Physical limitations in strength of blades and moving parts primarily controlled the size of the bores that could be advantageously bored or roamed with a single tool. Strength and full support of the blades is essential or at least desirable in that such is conducive to precision operation over an extended period or the life o f the tool. Reduction in the diametric size of the blades without weakening the strength thereof is the limitingk factor in the size range. To weaken the blade structure Wou1d,` when the operator forcedthe enlarging adjustment too vigorously, distort the blades and thehoning operations would be inaccurate, not circularly true, and unsatisfactory from a. mechanical standpoint.

Rigidity o f blade structure is important and to accomplish dependable, satisfactory honing operations over extended periods, increased honing size range should not'be accomplished to the detriment of' rigidity orraccuracy. This presents a problem; of combining normally oisetting fea-l tures, namely, increased rigidity tends to determine minimum size limits of the honing blades. The teachings of the present invention has. accomplished an increased range of honing operations. without sacrincing rigidity and honing accuracy. Y

One object of the. present invention is; to provide an abrasive reamer construction inwhich shoes or blades of widely different diameter or size may be substituted quickly and conveniently, so thatbut one reamer is required fora wide size rangefof honing operations.

Another object is to kprovide an abrasive reamer construction having a diametral expansion which can bey accurately and reliably gauged by almi-` crometer adjustment. to a small lfraction. of a thousandth part oi an inch Without the latter serving as an obstructionto small size honing diameters.

Still another objiect. is to provide an abrasive reamer, the expanding shoes. or blades of which are rigidly supported for substantially their entire length so that the reamer will nish a hole exactly true even under forced operations in an' increased range of honing sizes.

A further object is to provide a reamer With a readily detachable micrometer adjustment that will not limit or define the Aminimum size of honing attaina le with any reamer unit of wide size range.

A still further object is to provide an improved blade structure for an. abrasivereamer thaty cornbines rigidity with overall size rdiminution and interchangeability with blades of standard size range,

Still a further object is to prov-idean increased length blade `with aj minimum honing size diameter to accomplish v rigidity and increased size honing range with aV reamer of single reamer unit.

Other objects and advantages will appear from the following description of an illustrated embodiment of thepresent invention.

In the drawing:`

Figure 1 is averticalside view in elevation and partiallyin section of an abrasive reamer embodying features of the present invention.

Figure 2 vis a vertical edge enlarged sectional View in elevation taken substantially along line II-II of Figure 1.

Figure 3 is an enlarged side fragmentary viewy in elevation of the adjusting end of the reamer y with the shoes or blades assembled therewith, the

detachable micrometer adjusting instrumentalities being shown in dotted outline.

Figure 4 is a side sectional view of the other end of one of the blades or shoes taken substantially along line IV-IV of Figure 2. Figure 5 is a side view in elevation of the micrometer adjusting deviceV that is detachably associated with the end of the reamer and shown in dotted outline in Figure 3.

Figure 6' is an enlarged fragmentary side view in elevation of the adjusting vend of the reamer with one blade abrasivev shown in section and the other in full outline.

Figure '7 is a section of view taken substantially along line VIl--VII` of Figurey 2, one edge of an abrasive liner being shown unattached.

Figure 8 is a sectional view taken substantially along line VIII- V111 of Figure 2. f

Figure 9 is an edge view in elevation of the smaller blade size construction compared to the larger size blade construction shown in Figure 1.

Figure l0 is a plan viewof the improved small size blade shovvn in Figure 9.

The structure selected for illustration is not intended to serve as a limitation upon the scope or teachings of the invention, but is merely illustrative thereof. There may be considerable variations and adaptations of all or part of the teachings depending upon the dictates of commercial practice. rThe present embodiment comprises a body l@ with flat parallel sides II and tapered edges l 2 providing a large end I3 and a small end I d or" the convergingly tapered body Ill.v

rIhe small body end I@ terminates in an elongated threaded extension I5 over which a bearing sleeve le is disposed to extend short of its length to accommodate a retaining end nut ll against the sleeve I6. The retaining nut il' is somewhat larger in diameter than the bearing sleeve I6 which receives a substantially larger collar I8 thereover to freely rotate thereon against end displacement precluded by a composite fiber and steel washer l2 which is somewhat smaller than the collar i8.

To this end, the retaining nut Il has a diametrically extending screwdriver blade receiving slot therein to provide for the rotation thereof relative to the threaded extension I5.

The collar i8 has an enlarged peripheral exterior rounded shoulder 2l that is concavely endcupped as at 22 to receive complementari end blades therein as will appear more fully hereinafter. A rectangular driving shank- 23 extends from the large end I 3 of the tapered body li to terminate in a polygonal body 24 which is adapted to be placed in a chuck constituting a part of a power turning tool, such as a portable electric drill. The polygonal body 24 has an enlarged end 25, which has a substantially rectangular socket 26 provided therein of somewhat larger size than the end of the driving shank 23 to permit a limited degree of play or pivotal movement therebetween in all directions.

The enlarged cylindrical end of the polygonal driver 2li is retained in loose association with the free extremity of the driver shank 2B by means of a coupling comprising a cylindrical cap 21 that` has a central bore 28 somewhat largerv than the reduced shank 29 of the driver 24 and its Aenlarged end 25. The coupler cap 2l has an enlarged peripheral flange 3d that is complemental to the cylindrical coupler member 3l that is press iitted in the open bore 32 dened by the peripheral flange S0, thereby maintaining the driver 24 in loose association with the driver shank 23 in that the cylindrical coupler member 3! has its closed end 33 bored as at Se for pressfitted engagement with the driver shank 23, to establish its rigid joinder therewith.

The coupler member 3l is tted to the driver shank 23 in a position to provide a limited space 35 between the driver shank end and the bottom of the socket 2li provided in the driver end 25. This allows the driver 24 to move axially on the driver shank 23 and pivotally to a slight degree in all" directions owing to the fact that the socket 2S is somewhat larger than the driver shank 23 and the enlarged driver end 25 has an exterior diameter Y somewhat smaller than the interior chamber 35 of the coupler member 3l, so that limited universal movement is permitted between the driver shank 23 and its polygonal driver This minimum limited movement is desirable owing to the fact that true honing can be accomplished even though the operator holds the driven end somewhat out oi alignment with the power driver, such as a portable electric drill, as will appear more fully hereinafter.

The concavely end cupped blade receiving 4 socket 22 in the collar I8 is confronted by a similarly concavely cupped blade receiving socket 31 provided in a blade retaining collar 38, which has a bore 29 therethrough to receive the driver shank 23 therethrough and provide freedom of movement so that the retainer 38 will be free floating for support by a spring 49.

The spring 4l) is of a standard, convolute type which envelopes the driver shank 2.3 between the xed coupler member 2l and the floating blade end retainer 3S to urge the latter in the direction of the confronting blade receiving socket 22 in the collar I8.

A plurality of emery cloth supporting blades 40C-lll, in this instance two, are shaped as coinplements of each other and the tapered body I0 for retention between the end capped sockets 22-31 through the urge of the spring 2li. To this end the blades [MV-4I have arcuate projections lS2-ll3 and M -l5 provided at their extremities to conform in curvature, size and shape `with the capped sockets 22-31 for retention therein when the tapered body Il) is received in oppositely and complementally inclined grooves 46-4l provided in the confronting surfaces of the blades diy-4I throughout the length thereof. This enables the blades lV-2| to be seated throughout their entire length on the inclined edges I2 of the `body I0 with the spring 40 normally urging them toward the collar I8 to assume their minimum diameter expansion so long as the spring 40 is unopposed except for the collar i8' and its'retainer nut I 1 serving as a stop therefor.' v

A counter urge or force applied to the collar I8 will cause the blades 46h-Htc ride along the diverging edges I2 of the tapered body il! to e'ect their expansion or recession from each other, while the spring 40 is compressed to a corresponding degree. vIn this manner, the size of the bore to bve-honed can be predetermined by limiting the extent to which the collar I8 and the blades dll- 4I are displaced along the inclined body I0 inthejdirection of the driver 24, which is simultaneously rotated by a power instrumentality, such as a standard portable electric drill.

It should be noted that the tapered contact between the cuppedA socket ends 22-31 of the confronting members lf3-38, respectively, serve to hold vthe complemental blades or shoes IIIV1I together with their tapered channels or grooves iS- 41 in full contact with the taperededges I2 of the body I0 for the entire length of the blades or shoes lV-4 I. The channels or grooves 4-6-47 in the complemental blades 4'-4| have a close but free slidable t against the edges I2 and flat sides II of the body Il).

It should be noted that thegretainer end II on the'lbody extension I5 serves to limit the extent to which the blades or shoes 6L-4I may be displaced along the tapered body I0, and a calibrator is provided therefor to limit `the extent of displacement of the lbla-des INV-4I and their relative expansion to 'denne a predetermined diametrical honing size, to which a bore will be nished by the abrasive action of abrasive sheets 43-49 that are detachably associated with the blades or shoes lily-4I. ,To this end, the abrasive sheets S8-49 are provided with substantially U-shaped edge re-enforcing cleats 5Fl-5I that are clinched to the side edges of the abrasive sheets 48-49 to serve as attaching expedients therefor in conjunction with the blades or shoes 40-4l.

The cleats Sli-5I tightly t into side grooves 52-53 provided in the parallel side walls 54--55 of each of the'complemental shoes 40-4I. The

side grooves or channels 52.--53 extend substantially for the length of the blades or shoes 4I|4I proximate to the curved or arcuate abrasive sheet supporting surfaces 56 that constitute the external operating surfaces over which the abrasive sheets 48-49 are tensioned for support. This renders the abrasive sheets 48-49 together with their cleats `5l---5I removable for replacement with new abrasive sheets of corresponding size and structural characteristics.

Now, then, in order to adjust the blades 4Il-4I with their abrasive reaxning or honing surfaces 48-49 to the desired bore to accomplish the best results and to effect a predetermined expansion thereof to impart the desired finishing size, an elongated exteriorly knurled end bearing or manual handle sleeve k51 has .one of its open extrem ities 58 interiorlysized as at-59 for substantially the length of the collar I8 to freely fit thereover for rotation relative thereto without any appreciable looseness or play therebetween. The interna-l end bore 59 of the manual handle sleeve 51 which fits over the collar I8, terminates in a peripheral shoulder 50 dened by the somewhat smaller interior bore 5I that communicates with a somewhat larger collar bore 59 to denne the tubular manual handle sleeve 51. Y

The peripheral shoulder 60 contacts the cornposite thrust washer and limits the inward movement of the manual handle sleeve 51 relative to Ithe collar I8, so that the sleeve edge 58 meets with the rounded peripheral shoulder 6I! at the cupped end of the collar I8, thereby providing contact along the peripheral shoulder 5B and the open peripheral extremity 58 of the manual handle sleeve -51 with the collar I8 and its thrust washer I9.

A calibrated micrometer collar 52 is journalled on a reduced extremity 63 of the ymanual handle sleeve 51 for rotation relative thereto, it being retained thereon by an interna1 split spring 64 confined in an annular slot'65 of which complemental portions are in the confronting surfaces of the micrometer collar 62 and the sleeve extremity 63.

Consequently, the micrometer collar 62 is connected to and rotates relative to the manual handle sleeve 51. The micrometer collar -52 has an inwardly extending peripheral flange 66 at the outer extremity thereof to re-enforce the knurled peripheral edge 61 and t0 present a radially extending longitudinal rib 68 serving asa key disposed in a slot orv keyway 659 provided in and along an elongated stop screw 10 for the entire length thereof between a reduced inward tip1 stop 1I and an outward enlarged knurled head 12 serving as a turning expedient for the elongated stop screw 10.

With this arrangement, the stop screw 10 rotates with the micrometer collar 52 While in threaded engagement with an inwardly projected threaded cylindrical wall 13 provided in the extreme end region 63 of the manual handle sleeve 51. A retaining or lock nut 14 threadedly engages the stop screw 10 above the micrometer collar 62 to retain it 'in adjusted position relative, f to the manual handle sleeve '51 so that the latter may be displaced with the collar I8 and blades or shoes dll-4I a predetermined distance in the ydirectiono'f the driver member 24 lto compress the spring ,4G until the stop screw tip 1I engages the retaining nut I1 and this limits any further displacementof the lblades or shoes -4Il-4I rel: ative to the `tapered hone kbody ID. This limits the maximum relative :recession or expansion of the blades or shoes 4'-4I and thus determines the honing diameter of the finished bore.

The micrometercollar 62 may be calibrated to 5 any desired scale, but it is preferable, though not essential, to -Ioe graduated in .0025v inch and the pitchof the threads on the stop screw 10 and meshing threads 13 are such that one complete turnv of the stopI screw 10 is .005 inch. Other graduations or calibrations may be utilized, vbut thisis preferred.

In' adjusting the work to the hone, the stop screw 10 is screwed out so that theblades or shoes INV- 4Ik and their abrasive covers 48-49 are expanded to ll snugly the hole or bore to be honed, then the stop screw 10 is screwed in until its tip 1I will just touch the retaining nut I1 while the manual handle sleeve 51 is held against the tension of the spring 4i). The hone blades HIV-4I with their abrasive covers 48-49 are now set to the size of the hole or bore. Thereafter, the stop screw 10 is adjusted by turning the micrometer collar 62 in one or a repeated series of steps to the desired extent to which the hole or bore is to be finished.

Assuming the hole or bore is to be enlarged .003 inch, the stop screw 10 is backed out .003 inch, and the lock nut 14 is then screwed to engage the micrometer collar 62. With the driver member in the chuck of the power drill that is held securely in a visethe power is started to turn the hone body l!! with its blades 4ll-4I and abrasive covers Ail-119. `Force is then' applied on the f knurled manual handle sleeve 51 to expand the hone while the high speed rotation thereof gradually cuts the bore to the size by continuing the force or pressure on the sleeve 51 against or in the direction of the driver 24. The end :surface 15 of the enlarged head 12 on the stop screw 1II can be held against they operators body to steady the rotation while the work is held stationary in the operators hand relative to the rotating yabrasive surfaces 48-49 that are supported by the blades or shoes 4I. This force is continued or progressively applied until the Astop screw -10 has its tip 1IA in contact with the retainer-'nut I1. This determines the predeter-v mined size of the honed bore.

In order to hone bores that are smaller in di- '50 ameter than the manual handle sleeve 51 and the stop screw 10 preferably having an enlarged knurled head 12, the manual handle sleeve 51 is detachably associated with the collar I8 so that the hone I0 with its predetermined size of blades 55 40-4I may be displaced through the bore of the work, and thereafter the manual handle sleeve 51 replaced with its stop screw 10 and enlarged knurled head 12 having a smooth curved surface 15 serves as a suitable stabilizing influence when thebody of the operator is held thereagainst. It should be observed that the manual handle sleeve 51 serves as a manually supported end bearing which is removably and rotatively associated withv the collar I8 for unobstructed attachment and de tachment therewith as part of the hone body ,i5

to fully accomplish the specified function and Y purposes therefor. For instance, this arrangement permits the manual handle sleeve k5.1 to :be

7 0 removed in the ordinary use of the device to per` mit a bore of a wrist pin or a bea-ring comprising,

a vpartiof any other structural part or device to be passed over the abrasive sheets .A8-#49 `on the body Hl and, thereaftenthe manual handlesleeve l 51 is replaced on the body end orco'llar `I8,'there by enabling the honing of much smaller bore diameters than is otherwise possible.

So that full advantage may be acquired through the use of a detachable manual handle sleeve Fil', an improved blade structure has been provided that takes care of the smaller bore diameters without'req'uiring a smaller size hone body l0 to which rigid, thick, standard blades or shoes WL-l are adaptable to this end a much longer blade it (Figure 9) is utilized, so that the elfective abrasive cover supporting length il from the tip M to the shoulder 45 can be thinned down below the limits of the required rigidity to accommodate the same channel or groove 45 therein. By thinning down the' effective abrasive surface Ti, smaller diameters are provided and still the same channel or groove 46 is accommodated at the expense of strength and rigidity at this portion; however, the increased length of the blade 16 provides an inoperative and appreciably heavier portion 18 between the shoulder 45 and the extreme vextremity 45", which compensates in strength for the weakened reduced portion 'l'i that determines the minimum size bore that can be honed below that which was possible with the uniformly shaped blades or shoes fl-4l.

In the thinned down portion Tl, which carries the abrasive covers L18-19, the inclined channels d6 therein approach thev outer surface to an eX- tent that an opening 'i9 occurs therethrough just in front of the shoulder 45', but the increased thickness of the ineifective honing portion 'iii provides the necessary strength to compensate therefor and the comparative weakness of the thinned down portion 1l.

It should be noted, however, the blades or shoes 16 of increased length are accommodated by the samehone body l owing to the fact that in the smaller diameter blades or shoes 15,'the effective honing surface l1 is appreciably shorter than for the blades dill-I of standard'and uniform thickness throughout. In the smaller diameters to be honed, the length is notl an important factor and for that reason correspondingly shorter abrasive covers are provided which are constructed similar to the abrasive covers 48-49 and engage in corresponding side slots T9 provided for the effective length Ti of the blade or shoe 76.

Two complemental blades 75 of smaller shape and size, are carried by the tapered hone body edges I2, and the eiective honing portion 'Il of the blades or shoes 76 are provided proximate to the insert end of the hone body lll corresponding with the collar i8 which is cupped as at 22 to receive the corresponding end 44 of the blade or shoe 16.

It will thus be app-arent that the combination of improved blade or shoe structures 16 for small holes or bores together with the detachable speed sleeve l, provides a greater range of honing sizes for the body i0 than was heretofore possible owing to limitations determined by the speed sleeve and its adjusting head, as well as the design of the blades or shoes ASL-4H for any given hone body I.

It should be observed that different sizes in the uniformly shaped blades or shoes ddl-4E, as well as in the irregularly shaped blades or shoes 'l5 for smaller hones, are provided so that a range of hole diameters or bores of appreciably larger and smaller size limits can be effectively honed without requiring more than one hone body lll and its auxiliary parts.

While I have lillustrated and described a preferred embodiment of this invention, it must be understood that the `invention is capable of considerable variation and modication without departing from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

I claim:

l. In an adjustable abrasive hole-finishing cutting tool, the combination with a body, of a plurality of abrasive sheet supporting shoes adjustably associated with said body, actuator means interposed between said body and said shoes for expanding and contracting said shoes relative to each other, means on the end of said body for operating said actuator means, an unconnected end bearing removably and rotatively associated With said body for unobstructed operative attachment and inoperative detachment therewith to serve as a manual handle sleeve and calibrated means on said end bearing said calibrated means cooperating with said actuator means to control the expansion of said shoes to a predetermined limit from an initially set relative position.

2. In an adjustable abrasive hole-nnishing cutting tool, the combination with a body, of a plurality of abrasive sheet supporting shoes adjustably associated with said body,`actuator means interposed between said body and said shoes for expanding and contracting said shoes relative to each other, means on the end of said body for cperating said actuator means, an unconnected end bearing removably and rotatively associated with said body for unobstructed operative attachment and inoperative detachment therewith to serve as a manual handle sleeve and calibrated means on said end bearing, said calibrated means cooperating with said actuator means to control vthe eX- pansion of said shoes to a predetermined limit from an initially set relative position, said last named means comprising a sleeve journalled for rotation relative to said actuator means, a graduated slip collar on said sleeve, and a stop pin adjustably connected to said sleeve through said graduated collar.

3. In an adjustable abrasive hole-iinishing cutting tool, the combination with a body, of a plurality of abrasive sheet supporting shoes adjustably associated with said body, actuator means interposed between said body and said shoes for expanding and contracting said shoes relative to each other, means on the end `of said body for operating said actuator means, an unconnected end bearing removably and rotatively associated with said body for unobstructed operative attachment and inoperative detachment therewith to serve as a manual handle sleeve and calibrated means on said end bearing, said calibrated means cooperating with said actuator means to control the expansion of said shoes to a predetermined limit from an initially set relative position, said end bearing comprising a sleeve journalled for rotation relative to said actuator means, a graduated slip collar on said sleeve, a stop pin adjustably connected to said sleeve through said graduated collar, and means interposed between said collar and pin toinsure theirconnected rotation as a unit while permitting the longitudinal displacement of said 'pin through said collar.

4. In an adjustable abrasive hole-finishing cutting tool, the combination with a-body, of a plurality of abrasive sheet supporting shoes adjustably associated With'saidbody, actuator means interposed between said body and said shoes for anregen eff expanding andfcontractingsaid shoesv relative toeach other, means on rtheend of said body for operating said actuator means, an unconnected end bearing removably and rotatively associated with said body for unobstructed operative attachment and inoperativedetachment therewith to serve as a manual handle sleeve and calibrated means on said end bearing, said rcali-brated means cooperating with said actuator means to control the expansion of said shoes to a predetermined limit from an initially set relative position, said end bearing comprising a sleeve journalled for rotation relative to said actuator means, a graduated slip collar on said sleeve, a stop pin threadedly connected to said sleeve through said graduated collar, and a key andkey-way interposed between said collar and pin to insure their connected rotation as a unit while permitting the longitudinal displacement of said pin through said collar.

5. In a cutting tool having a. central body with tapered faces and shoes provided with abrasive members tting thereon, cupped member on said body and fitting over the ends of said shoes to retain said shoes around said body, a spring positioned upon and along said body to bear against one of said cupped members, an adjusting member threadedly engaging said body and adapted to bear against the other cupped member, and an unconnected calibrated manual hand end bearing supporting sleeve removably and rotatively associated with said adjusting member for unobstructed attachment and detachment therewith to serve as a manual handle sleeve end support and stop for said adjusting member.

. 6. In a cutting tool having a central body with tapered faces and shoes provided with abrasive members iitting thereon, cupped member on said body and fitting over the ends of said shoes to retain said shoes around said body, a spring positioned upon and along said body to bear against one of said cupped members, an adjusting member threadedly engaging said body and adapted to bear against the other cupped member, an unconnected calibrated manual hand end bearing supporting sleeve removably and rotatively associated with said adjusting member `for unobstructed attachment and detachment therewith to serve as a manual handle sleeve end support and stop for said adjusting member, said calibrated speed sleeve including a slip collar, and a stop screw extending through said slip collar and threadedly engaging said speed sleeve.

7. In a cutting tool having a central body with tapered faces and shoes provided with abrasive members fitting thereon, cupped member on said body and tting over the ends of said shoes to retain said shoes around said body, a spring positioned upon and along said body to bear against one of said cupped members, an adjusting member threadedly engaging said body and adapted to bear against the other cupped member, an unconnected calibrated manual hand end bearing supporting sleeve removably and rotatively associated with said adjusting member for unobstructed attachment and detachment therewith to serve as a manual handle sleeve end supportr and stop for said adjusting member, said calibrated speed sleeve including a slip collana stop screw extending through said slip collar and threadedly engaging said speed sleeve, and an enlarged finger grasping knob on said stop screw to present a body contacting surface for assisting in the support of said speed sleeve.

8, In a cutting tool having a central body with a thin abrasive sheet carrying tapered faces andshoes provided with abrasive members fitting thereon, cupped member on said body and iitting over the ends of said shoes to retain said shoes around said body, a spring positioned upon and along said body to bear against one of said cupped members, an adjusting niember'threadedly engaging said body and adapted to bear against'v the other cupped member, an unconnected' calibrated manual hand end bearing supporting sleeve removably and rotatively associated with said adjusting member for unobstructed attachment and detachment therewith to serve as a manual handle sleeve end support and stop for said adjusting member, said calibrated speed sleeve including a slip collar, a stop screw extending through said slip collar and threadedly engaging said speed sleeve, complemental means on said collar and screw to insure their combined rotation while permitting relative axial displacement therebetween.

9. In a cutting tool having a central body with tapered faces and shoes provided with abrasive members fitting thereon, cupped member on said body and iitting over the ends of said shoes to retain said shoes around said body, a spring positioned upon and along said body to bear against one of said cupped members, an adjusting member threadedly engaging said body and adapted to bear against the other cupped member, an unconnected calibrated manual hand end bearing supporting sleeve removably and rotatively associated with said adjusting member for unobstructed attachment and detachment therewith to serve as a manual handle sleeve end support and stop for said adjusting member, a polygonal driver member operatively connected to said body on the end opposite said adjusting member for rotation therewith, and a collar coupler fixed to said body to engage said driver against detachment from said body while permitting slight relative universal movement therebetween,

10. In a cutting tool having a central body with tapered faces and shoes provided with abrasive members tting thereon, cupped member on said body and iitting over the ends of said shoes to retain said shoes around said body, a spring positioned upon and along said body to bear against one of said cupped members, an adjusting member threadedly engaging said body and adapted to bear against the other cupped member, an unconnected calibrated manual hand end bearing supporting sleeve removably and detachably associated with said adjusting member for unobstructed attachment and detachment therewith to serve as a manual handle sleeve end support and stop for said adjusting member, polygonal driver member proximate to end of said body opposite said adjusting member, complemental means on saidy driver member and body end to establish a driving connection between said driver member and body end while permitting their longitudinal separation, and a coupler fixed to said last named body end to embrace said complemental means for retaining said driver and body end together against separation while permitting slight relative universal movement therebetween.

ll. In a cutting tool having a central body with tapered faces, and abrasive supporting shoes adjustably fitted upon said faces, said shoes having portion sized to substantially conform with the dimensional limits of said tapered body surfaces and a substantialf ly thicker portion beyond and contiguous to said abrasive sheet carrying thin portion to compenabrasive sheet carrying thin portion, there being,

a tapered slot in the bottom surface of and extending for the overall length of said shoes to serve as a complement of said tapered body surfaces With the thicker shoe portion serving to compensate for the requisite overall body strength of said abrasive supporting shoes in relation to said tapered slot.

ANTHONY OBERHOLTZ, JR.

Images