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Publication numberUS568277 A
Publication typeGrant
Publication dateSep 22, 1896
Filing dateMar 24, 1896
Publication numberUS 568277 A, US 568277A, US-A-568277, US568277 A, US568277A
InventorsFrederick A. Rall
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Frederick a
US 568277 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

l the threads themselves.




'SPECIFICATION forming part of Letters Patent No. 568,277, dated September 22, 1896.

Application filed March 24, 1896.

To all whom, it m/cty col/Learn:

Be it known that l, FREDERICK A. RALL, a citizen of the United States, residin g at Tyler, Smith county, Texas, have invented certain new and useful Improvements in Tools for Cleaning Out Nuts, of which the following is a full, clear, and exact descriptiou, reference being had to the accompanying drawings, in which- Figure 1 is a side elevation of the tool. Fig. 2 is a section on line x fr, Fig. 1. Fig. 3 is a section on' line y y, Fig. 1; and Fig. 4 is a view similar to Fig. 1, but in which the tool is shown as it would appear after considerable use.

My invention has for its object to provide a tool for cleaning out internally-threaded apertures so as to refresh the screw-threads by removing all rust and dirt from between them and from off the edges thereof, and that without in any way destroying or Changing Heretofore it has been customary to clean out such screwthreaded apertures byan acid bath, by heat, and also by means of a screw-tap, but so far as I am aware there has been no special tool for this purpose.

I am aware of the tapering longitudinallygrooved tap having an integral bit or reamer on its end; also, that such tapering taps have had a plain or partially-threaded entering end or point, and that they have also had removable reamin g cutters; but in all such tools the tap begins with a tapering threaded portion which may or may not merge into a straight threaded portion. It follows, therefore, that when the tapering or feeding end of such combined reamers and taps become dull the tool becomes useless, and it will also be seen that if such a tap was used to clean out internally-threaded apertures the threads on its tapering end would not only become dulled, but would force the rust into the 'bottom of the grooves, from whence it cannot be removed until the last threads of the tap are engaged therewith, as they are the only ones which will reach the base of the threads. Hence it follows that the entire tap would be dulled and rendered useless and, moreover, the threads of the nut would be cut and enlarged thereby, so that the nut would fit Serial No. 584,616. (No model.)

loosely on its bolt. As these taps are far more expensive than a large number of nuts it does not pay to ruin them in attempting to clean nuts with them. v

With these objects in view and the foregoing difficulties to overcome my invention consists in a tool provided with a plurality of longitudinal ribs having straight nontoothed reaming edges at the front end and transverse teeth in rear of the reaming ed ges and all of the same depth, the base-line of the teeth being i-n the longitudinal plane of the said reaming edges and the points of each row of teeth terminating on a line parallel with the longitudinal aXis of the tool,

so that when the tool is introduced into a will enter the threaded groove and thoroughly clean it without Changing the thread, said first tooth when dulled being ground off to thus lengthen and freshen the reaming edge and present a new tooth for the operation of cleaning.

In the drawings, A is the shank of the tool, squared at its rear end to receiV-e an operating handle or device. A' are four longitudinal ribs at the threaded front or working end of the tool, formed by grooving the shank longitudinally for the required distance. The front portions of these ribs form a reamer B, and the working edge b of each reamerblade is parallel with the longitudinal axis of the tool, and the tool at this point will be of the same size or circumference as the bore of the threaded aperture to be cleaned, so that the reamer will not cut out or reduce the threads at all, but will only remove adhering rust or dirt from their edges.

O are the teeth formed on the ribs A' immediately at the rear or inner end of the reamer B, and the base-line of each row of teeth is parallel with the longitudinal axis of the tool and in the same longitudinal plane as the adjacent reaming edge b, while the outer ends or edges of the teeth of each row terminate on a line parallel with the longitudinal axis of the tool. That is, all of the teeth are of the same depth and are shaped to fit the internal threads just as a bolt would the foremost tooth O will have to act in cleaning or refreshing an internal thread, ``said tooth following the groove in the nut or aperture and removing all dirt, rust, tc. As soon as this first tooth becomes dull it will be ground off and the blank space left thereby will form a part of the reamer, as shown in Fig. 4. Thus while the teeth grow fewer in number the reamer Will be correspondingly refreshed by a new and sharper reaming-surface. This operation may be continued till the last tooth is removed.

The extremity of the reamer B is slightly rounded to permit the tool to be more readily introduced into the threaded aperture, and as the reamer snugly fits the bore thereof it will serve as a guide to center the tool and cause its tooth to enter the groove of the internal thread.

This tool will not drll nor will it tap a thread into an aperture, nor Will it remove a previously-formed thread and cut a new one, but is designed for the sole purpose of cleaning a `previously-formed internal screwthread.

W'hat I claim is- A tool for cleaning internally-threaded apertures Without Changing the threads thereofI` consistin g in a shank provided at its working end with a plurality of straight longitudinal ribs,the front portions of which constitute reaming cdges parallel with the longitudinal axis of the tool, and the tool in rear of said reaming edges being threaded and forming thereby a series of teeth on each rib; all of the teeth thus formed being of the same depth, with the base-line of each row in the longitudinal plane of the alined reaming edge; said threaded or toothed portion being constructcd to fit the internally-threadcd aperture to be clcaned, after the manner of its bolt, to cause the first tooth to act as the cleaner, substantially as set forth.




Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2530268 *Aug 14, 1945Nov 14, 1950Western Electric CoTapping apparatus
US2948000 *May 28, 1957Aug 9, 1960James H BorlandRefinishing tool for tapped hole and seat
US3195155 *Nov 26, 1962Jul 20, 1965Bendix CorpProcess of threading an opening
US3464072 *Nov 7, 1966Sep 2, 1969Schellstede Herman JThread form restoring tool
US5562371 *Jun 7, 1995Oct 8, 1996Lock-N-Stitch InternationalTap with a non-cutting pilot
US6231281 *Dec 11, 1998May 15, 2001Honda Giken Kogyo Kabushiki KaishaThread milling cutter with drilling edges
US6261039Oct 2, 1996Jul 17, 2001Gary Jack ReedThread repair insert
US6435788Mar 19, 2001Aug 20, 2002Gary Jack ReedThread repair insert
US6439817Mar 19, 2001Aug 27, 2002Gary Jack ReedInsert retention mechanism
US20120003054 *Feb 20, 2009Jan 5, 2012Toyota Jidosha Kabushiki KaishaTap with drill and method for cutting internal thread
Cooperative ClassificationB23G5/06