US1479484A - Reamer - Google Patents

Description

E. C. SCHMELZKOPF REAIIER Filed-Nov. 13. 1922 2 Sheets-Sheet 1 Jan. I 1924 l.479,484

Ira/anion Fag/aid Jaime/2h,

Patented Jan. 1, 1924.

UNITED STATES PATENT OFFICE.

EDWARD C. SCHMELZKOPF, OF MADISON, WISCONSIN, ASSIGNOR TO GISHOL'I' MACHINE COMPANY, OF MADISON, WISCONSIN, A CORPORATION OF WISCONSIN.

amen.

Application filed ll'ovember 13, 1928. Serial Io. 800,771.

To all whom it may concern:

Be it known that I, EDWARD C. SGHMELZ- KOPF, a citizen of the United States, residing at Madison, in the county of Dane and State of Wisconsin, have invented certain new and useful Improvements in Reamers, of which the following is a specification.

This invention relates to improvements in reamers, and has reference more especially to tools of that type which are employed to finish, smooth and size a hole in various metals. It is well known that in the use of such tools, after a .reamer has finished a number of holes the sharp cutting edges of the tool begin to wear, and the diameter of the hole in the work is thereby reduced a fraction of a thousandth of an inch. In order to keep the hole in the work to a standard dimension, a reamer must be quickly and accurately adjusted to its normal diameter. The main object of the present i'nventionis to provide an im roved reamer that can be adjusted or re-sizeg more easily and in much less time than is required for an similar reamer now known.

Another ob ect of the invention is to provide, in a reamer of this type, a bladeclamping device that will not only allow endwise adjustment of the blade to increase or decrease the cutting diameter of the tool but will also automatically take care of slight variations in the clampin lengths of the blades, and will also ena le slight adjustments of the cutting diameter to be made, without requiring any shifting of the disc clamp at the lower end of the reamer relatively to the body of the tool. A still further object of the invention is to provide a reamer of this type in which the blades will be rigidly held in place in all adjusted positions, so that they will be practically as solid and immovable as they would be if made integral with the body.

In order that my invention may be readily understood by machinists and others skilled in the art of machine tools, I have, in the accompanying drawings, illustrated two practical embodiments of the invention which have been found to satisfactorily effectuate the stated urposes and objects thereof; and referring t ereto Fig. 1 is a side elevation, in axial section through its upper half, of a reamer embed ing my invention, and in which the bla e slots and blades are formed with parallel sides;

Fig. 2 is an end elevation of the complete tool, viewed from the right of Fig. 1;

Fig. 3 is a half section on the line 3--3 of Fig. 1.

Fig. 4 is a top plan of one of the blades;

Fig. 5 is an end elevation of the blade shown in Fig. 4 viewed from the lower end of the latter;

Figs. 6, 7 and 8 are views corresponding with Figs. 1, 2, and 3, res ectivel showing a reamer wherein the lads s ots and blades are tapered both longitudinally and transversely;

Fig. 9 is an inner side elevation of the blade clamp disc, which is the same in both forms of rcamer shown;

Fig. 10 is a top plan of the blade shown in Figs. 6, 7 and 8;

Fig. 11 is a side elevation of the same blade as viewed from the bottom of Fig. 10; and Fig. 12 is an end elevation of the same blade viewed from the right of Fig. 11.

In both forms of the invention shown, the reamer comprises essentially a body formed with longitudinal blade slots, blades slidably fitting said slots and formed with inclined end wall portions to secure an inward camming effect under endwise pressure b the clamping and holding devices, a bla e adjusting ring threaded on the inner end of the reamer body and formed with a tapered or beveled inner side engaged with the inclined rear end walls of the blades, and a transversely elastic blade clamp disc attached to the outer end of the body preferably by screws passed therethrou h and into tapped holes in the body, and iormed with a circumferential flange having a beveled or tapered inner side engaged with under-cut cam surfaces on the outer end walls of the blades.

Referring first to the form of the inven- I Ill slots 14 in its circumference, these slots be ing arallel with the axis. The side walls of tie slots are parallel throu bout, and their bottom walls 15 are forms on a low outward taper or incline from points near the inner end to the outer end thereof as clearly shown in Fig. 1.

The blades 16, of which one is shown in detail in Figs. 4 and 5, are formed of a uniform width to accurately fit the side walls of the slots 14, and each blade has a tapered or inclined bottom wall 17 that lies in contact with the inclined bottom wall 15 of the blade slot. On its outer side each blade has a. cutting edge 18, herein shown as oblique, but, of course, the cutting edge may be oblique, arallel or spiral, as desired, since this detail is immaterial to the present invention. Each blade has at its inner end a downwardly and rearwardly inclined end wall portion 19, and at its outer end an under-cut downwardly and forwardly inclined end wall portion 20.

The inner end of the reamer body is externally threaded for some distance, as shown at 21, and mounted thereon is a! blade-adjusting ring'22 havin an inner beveled side 23 that fits the inc ined end wall portions 19 of the blades and, when the adusting ringA blades len wise in their slots in an obvious and well-known manner; this adjusting ring being quite common in reamers of the ty e. The adjusting ring 22 may be provided with a scale indicated in Fig. 1 b which the fine adjustments of the cutting iameter efi'ected by turning lip the ring may be accurately determined. ounted on the body behind the adjusting ring 22 is an ordinary locking rinig 24 to prevent accidental loosening of the a justing ring 22.

To the forward end of the reamer body is attached by clamp screws 25 an annular disc clamp designated as an entirety by 26. This clamp is formed with a short inwardly extending peripheral flange 27 that has a beveled or tapered face 28 fitting the undercut tapered or beveled end portions 20 of the blades. The reamer body is formed with tapped holes 29 in its outer end to receive the screws 25; and the disc clamp 26 is formed with countersunk holes 30 to receive the tapered heads 31 of the screws. Preferably each screw is formed with a central hexagonal socket 32 in its head for the application of a wrench but the particular formation to accommodate a screw driver is immaterial. j

The disc clamp 26 is made of highl tempered steel and sufiiciently thin to a 0rd a slight. transverse bending capacity in any direction. In a. reamer having an: blades three of these clamp screws are preferably employed, one mid-we between each pair of adjacent blades, as own in Fig. 2.

is screwed up, advances the The manner in which the blades are rigidly held while working, and the manner in which the cutting diameter may be increased or decreased, will be readily apparent from the foregoin but may be briefly outlined as follows. l'iith the disc clamp 26 in place, the adjusting ring 22 is turned up until the blades are rigidly clamped endwise by the oppositely tapered walls 23 and 28 of the adjusting ring and disc clamp respectively, which by a camming action draws each blade downwardl onto the bottom wall of the blade slot. f this does not ive the exact desired cutting diameter the atter may be increased by backing oil the disc clam sli htly and correspondingly turning up tie a justing ring; the reverse of these adjustments obviously effecting a decrease in the cutting diameter, the outward and inward radial movements of the blades that occur simultaneously with their longitudinal movements resulting, of course, from the co-operation of the inclined bottom walls of the blades with the inclined bottom walls of the slots. If the clam lengths, (by which is meant the distance between the tapared end walls 19 and 20) of the several lades are not exactly the same, very small variations can be taken care of by further tightening of one or more of the disc clamp screws 25, which thereby produces a slight inward bending of the clamping flange 27 tofit the blade or blades that are slightly ,under normal clamping length. Moreover, a very slight increase of cutting diameter can be effected by the application of increased pressure at the inner ends of the blades by further turning up the adjusting ring 22 alone, the peripheral portion of the disc clamp 26 sprin ing outwardly sufilciently to permit such ne adjustment without resetting the clamp screws 25. To eflcct adjustments of any substantial amount, however, the ositions of both the ring 22 and the disc 0 amp 26 must be shifted endwise of the reamer body.

The form of the invention illustrated in Figs. 6 to 12 inclusive embodies identically the same structural characteristics, so far as the blade-clamping devices are concerned, as the form shown in Fi 1 to 5 inclusive and alread described. 15: this form of the invention, owever, one side wall 33 of each blade slot, instead of being parallel to the o posite wall, is inclined outwardly relatively to the opposite side wall, as clearly shown in Fig. 8 thereby producing a slot of decreasing width from to to bottom, or of wedge shape. The radia y inclined wall 38 is slightly i clined lon 'tudinally relatively to the opposite side we exce at its lower edge which is parallel with 1'. lower edge of the opposite wall,.so that the slot, except at its bottom is slightl wider at its rear or inner end than at its orward. or outer end,

this characteristic of the slot appearing in perspective in Fig. 7. The blades 16', of which one is shown in detail in Figs. to 12, of course have side walls corres onding with and adapted to fit the side wal of the blade slots; the side wall 34 thereof tapering radially and also longitudinallfi, except at its lower edge, so as to be para el throughout with the correspondingly tapered side wall 33 of the slot.

By reason of the transverse or radial wedge formation of the blades and blade slots, the inward clamping action of the adjusting ring 22 and the disc clamp 26 draws the blades very tightly into the slots and clamps them in wor ring position with great rigidity. When the cutting diameter is increased or decreased by outward or inward endwise adjustment ofthe blades, the radial adjustment of the latter is efiected by the lon itudinal. taper of the co-operatin side walls 33 and 34 of the blade slot and blade, rather than by any co-operation between the inclined bottom walls of the slot and blade which are out of contact. This construction has the advantage over the construction shown in Figs. 1 to 5 inclusive, of clam ing the blades under a wedging fit of the b ades themselves in their slots, so as to obtain even greater ri idit of the blades relatively to the body t an In the first described stucture. So far as the blade clampin means are concerned, however, these are i entical with the construction first described.

I claim- 1. In a reaming tool, the combination with a body formed with longitudinal blade slots,

of blades fittin said slots and formed with beveled end wa s, each of said slots and its blade havin contacting walls that are inclined len wise relatively to the axis of the bod whereby endwise adjustments of the bla es are accompanied by radial ad- 'ustments thereof, a ring threaded on said y and formed with a beveled inner side fitting and embracing the rear beveled end walls of. said blades, and a transversely elastic disc clamp op site and adjustably secured to the forwar end wall of said body and having an inwardly directed eripheral flange formed with a beveled side ttin and embracing the forward beveled end we of said blades.

2. In an ad'ustable reamer, the combination' of a y formed with longitudinal blade slots, of wedge-shape both lengthwise and crosswise and narrowest at their bottoms, the longitudinal edges or the bottoms of said slots bein parallel, blades of corresponding wedge-s ape fitting said slots with their bottom walls out of contact with the bottom walls of the latter and formed with beveled rear end portions and oppositely beveled undercut forward end gortions, an adjusting ring threaded 0n sai 7 body and in thrusting and clamping engagement with the rear beveled end portions of said blades, and a transversely elastic annular disc clamp opposite and adjustably attached to the forward end of said body and formed with a peripheral flange in thrusting and clam ing engagement with the undercut forward eveled end ortions of said blades.

E WARD C. SCHMELZKOPF.

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