US1388490A - Rotary earth-boring drill - Google Patents

Description

j. R. EIUII'HIIII` ROTARY EARTH BORING DRILLI APPLICATION FILED SEPT. In, 1920.

MSAIQUI PIII-mixed Aug 23. 19251@ NOQ JOH/V R 5U/VAN INVENTOR.

ATTORNEYS.

lll

UNITED STATES PATENT OFFICE.

JOHN' R. SUMAN, 0F HOUSTON, TEXAS.

ROTARY EARTH-BORING DRILL.

Application flied September 18,1920. Serial No. 411,180.

To all whom t may concern Be it lrnown that L JOHN R. SMAN, a citizen ot the United States, residing at lllouston, ltlarriscounty, Texas, have invented a certain new and useful Improvement in ltotary Earth-Boring Drills, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same.

lilly invention relates to an improvement in drills tor boring in earth, roch, or other similaratormations in the digging of wells tor water., oil, gas, etc.

ldy drill fs designed as a combination bit tor use in material of ditlerent degrees ol hardness. llt is an object of my invention to design a drill for well digging which 1s adapted to work in different characters ot -formation and to cut the strata evenly and with a minimum amount of vibration.

another object is 4to provide a tool ot this character havin@n cutting means which are easily removable and replaceable when worn.,

another object is to provide a device ot* this character which will have means to discharge'the tlushing fluid at numerous points upon the'surtace being out and in such manner as to wash the material directed from the cutting points. i vantages will appear from the description which follows:

lhieterring to the drawing, wherein like numerals ot reference are applied to like parte throughout the several views, Figure l is a central longitudinal section through a drill hit embodying my invention, talren on the line l-l of Fig. 2; Fig. 2 is a bottom alan view ot my invention; llig. 3 is a central longitudinal section of a broken portion oi? the bit showing one of the cutting teeth and its method oi'attachment; Fig. l is a top plan view ot one ott the cutting teeth; and lig. 5 is a view Showing a modilied means ot attaching the cutting teeth to the bit.

lln the drawing I have illustrated the preterred embodiment of. my invention, in which ll have a head l, somewhat cup-shaped in construction, and having the upper open end thereo'lE threaded at 3 tor attachment to a drill astem .93. The cutting teeth il ot my drill project radially from the outer surface Other objectsA and ad of the cup-shaped head so as to present theappearance of a flattened hemisphere with peg-shaped projections covering the outer surface thereof.

The cutting teeth are practically cylindrical in. shape intermediate their ends, the outer cutting portion being beveled, as

sho-wn particularly in Fig. 3, the beveled the bit, the teeth extending laterally, as'

shown at l in Fig. l, perform the larger part ot' the cutting action with the lower edge ot the cutting iace and, to allow tor this fact, the cutting tace is wider toward the lower portion of these teeth than at the upper portion, as will be noted in Fig. l. The teeth are secured in position by having theinner end 8 enlarged somewhat and htted within a recess 9, shaped to receive the same on the inner tace of the head l. The recess Sl, and the enlargedportion 8 litting therein, are shaped somewhat oval, as shown in Fig. so as to prevent rotation of the cutting tooth when 'fitted in position.

To retain the teeth in operative position when they have been placed within the head, l provide a cup-shapedv retaining member l0, spaced to lit closely against the inner face ot the head Il so as to bear against the inner ends ciA the teeth and hold them se- -lit within openingsV i8, formed to register withthe said dowel pins and receive the same. ln the central portion ot the outer lace of the head l, l have formed a threaded 'recess ll, into which l screw a specially termed tooth or pilot bit l5, the said tooth being llattened in the manner ot a fish tail liti lllll ltlti bit and pointed so `as to form a pilot member adapted `to center and guide the bit and also to cut away efficiently the material at the center of the hole. rllwo central channels 16 for 'lushin water are provided longitudinally of this cutting tooth so as to eiiciently clear the same of material.

As will be noted from Fig. 1, the teeth fitting against the rounded outer face of the cup-shaped retaining member 10 do not con* form to theshape of the retaining member :and in order to remedy this I contemplate I contemplate forming vthe same with concaved inner faces, conforming with the shape of the retaining member. In Fi 5, I have-shown a different means of attacing the cutting teeth withinV the head. In this embodiment, the inner end is threaded at 19 for attachment within the head, it bein contemplated that the teeth will be scnewe firmly within the head until the cutting face is directed in the proper position for cutrlie flushin water for the bitis pumped downward] t rough the hollow drill stem and throng holes 20 in the retaining member and -the channels 6 in the teeth so as to be projected directly against the cutting faces thereof. As will be seen, it is possible tol form the holes 20 in the retaining member to register with the downwardly directed` cuttingl teeth and to omit such openings in the upper rows of teeth, which are directed laterally, it beingl contemplated that the fiushingwater, directed toward the forward cutting ed e, will be suiiicient towash these, teeth whic perform the larger part `ofthe cutting action, and t0 alsofiush away the cuttings lfrom the upper teeth. It is obvious, however, that if desired openings 20 lmay be formed to register with the ends of the cutting teeth at the sides of the head also.

When theteeth are fitted in position, the recesses 9,'into which the heads-8 of the cutting teeth fit, will be formed in such manner that the teeth will present the cutting face in a direction radial from the center of the bit and directed forwardly'in thedirection of rotation of the bit so as to `bring the cut* ting edge 5 into contact with lthe material in the most efficient manner. Thus when the bit is rotated theteeth 4 will act upon the 'material at the bottom of the hole and act to disintegrate the material so that it may be washed away by streams of iushing water pumped downwardly through the 'bit and through the channelsV in the cutting teeth, so as to wash the cutting edge thereof and to carry the material in suspension upwardly outside of the drill to themsurface of the ground. Incase an of the cutting teeth'become dulled, it will be possible to quickly unscrew the head, remove the retaining member and sustitute new teeth for the dulled or broken teeth, and proceed with the drilling. This form of drill will be easy torepair and smooth and efficient in its action and, will not be liable to become balled up by material clogging thereabout.

Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A rotary earth boring drill comprising a head, radially projecting teeth on the outer face thereof, said teeth having cutting edges presented forwardly in the direction of rotation and means to discharge fiushing water against the cutting edges of each of said teeth. f

2. A rotar earth boring drill comprising a cup-shape head, teeth projecting radially from the forward end 'of said head, an enlarged inner end on each of said teeth fitting within recesses on the inner face of said head and a retaining member bearing against said head,- said teeth having sharp cutting edges presented in the direction of movement thereof.

5. A rotary earth-boring drill comprising the combination of adrill stem, a cup-shaped head secured thereon, cutting teeth projecting outwardly from said head,and a cupshaped retaining means lining the inside of said head, said retaining means being held in fixed position against said teeth by the lower end of said drill stem.

6. A rotary earth boring drill comprising the combination of a drill stem, a cup-shaped head secured thereon,cutting teeth projecting through said head, a retaining means fitting closely against the inner face of said head, said retaining member, head and teeth having registered channels to/conduct flushinghwater onto the cutting points of saidteet 7. A rotary earth boring drill comprising a hollow head, teeth projecting radially therefrom in forward and lateral directions, said teeth having oval shaped inner heads M mmm id'tdmg im @wd recesses in said Madd .mnd mmm m www Smid teeth 'm position.

d. www @nmllmborilng drill compsmg d MOHUW Madd, and mdadly projctngj =1 md-,h mounted mmombly in mid' head, said www having Mh@ llowm' ends 'bevled t0 pr@- mm :nllwzwd Sham@ cutting edges 'im th@ Wold@ ELU

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