US2086397A - Drill bit - Google Patents

Description

July 6, 1937. F, A AHE 2,086,397

DRILL BIT Filed June 22, 1935 EH4 Tia/a Q/d Patented July 6, 1937 DRILL BIT v Fer-i A. 'l'halieid, Dallas, Tex assignor to The Guiberson ration of Delaware Corporation, Dallas, Tex" a 60m- Application June 22. 1935, Serial No. zuzc and useful imimproved drill bit which may be readily assem- 5 bled or dis-assembled and which carries the usual conical cutters and is particularly adapted for use in drilling in hard formation during well drilling, or the like.

An important object of the invention is to provide an improved mounting for the conical cutters of a drill bit which provides an increased area for bearing the thrust against said cutters occasioned by the drilling operation, whereby the life of the drill is increased.

A further object of the invention is to provldean improved drill bit having conical cutters mounted thereon, the mounting including elongated rollers on which the cutters are rotatable, whereby an increased bearing surface for each 20 cutter is provided. I

A still further object of the invention is to provide an improved drill bit having conical cutters and including a split body having the cutter shafts carried at its lower end, the split body 25 permitting the easy dis-assembling of the bit toremove or replace cutters when worn, or for any other reason.

, A construction .designed to carry out the invention will be hereinafter described, together '30 with other featm'es of the invention. I

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawing. in which an example of the invention is shown, and

'35 wherein:

Figure l is a view partly in elevation andpartly in section of a drill bit constructed in accordance with the invention,

f Figure 2 is a horizontal, cross sectional view, 40 taken on the line 2-2 of Figure l, and,

Figure 3 is a transverse, sectional view, taken on the line 3-3 of Figure 1.

In the drawing, the numeral iii designates a split body including complementary sections or 45 halves A and B. Each section is semi-circular in cross section, whereby when placed together a circular drill bit body or head having a vertical bore ll extending therethrough, is formed. The upper end of the body is provided with a reduced, 50 tapered pin i2 which is threaded to receive the drill stem. Since the pin is smaller in diameter than the body, an outwardly directed shoulder I3 surrounds the lower end of said pin. It is pointed out that the pin could be eliminated and 55 any other suitable drill stem connection substituted therefor. For securing the sections A and 3 together,

the lower end of the bore ll of the body is provided with an annular, depending flange ll. The

60 outer end of the flange is beveled at I! as is 4 Claims. (C 255-11) shown in Figure 1. The upper end of the bore is provided with a similar flange I6. An elongated tubular connecting sleeve ll extends through the bore ii and has an enlarged collar i8 'onits lower end. This collar has an internal annular groove is which is arranged to be engaged by the annular flange It at the lower end of the bore. The groove has one face beveled complementary to the bevel ii of said flange.

The upper end of the connecting sleeve extends upwardly above the upper end of the bore and is screw-threaded to receive a collar 20. The

collar is provided with an annular groove 20'.

in its under side and when said collar is tightened down, said groove is engaged by the annular beveled flange l8 at the upper end of the bore.

It will be seen by observing Figure 1, that when the connecting sleeve is passed through the bore II as shown, and the collar 20 screwed onto its upper end, the two sections A and B will be securely clamped together by the collars l8 and 20 engaging the annular flanges l4 and It. It is noted that the complementary bevels of the flanges and grooves in said collars serve to draw the sections together, whereby a tight connection therebetween is provided. The engaging faces of the sections may be machined so that a.

fluid tight joint is had therebetween. Each section is formed with a depending leg or hanger 2| and when the sections are secured together the hangers are' located, diametrically opposite each other. Since the hangers are constructed exactly alike a description of one will sumce. As is obvious by observing Figure 1, each hanger has its inner face 2| inclined upwardly toward the center of the body. This inner face is flat and substantially circular in cross section, being provided with an axial opening ,22. Each hanger has the conical cutter 23 mounted thereon and. this mounting is one of the features of the invention.

Each cutter is provided with an axial bore 24 which extends partially through said cutter from the base thereof and this bore is provided with an annular recess 25 in its side wall. The axle 26 on which the cutter is mounted is made separate from the hanger 2| and has an external, annular flange 21 formed thereon. An axial recess 28 is located in the face 2| of the hanger and this recess is of the same diameter as the adjacent upper end portion of the axle 26, whereby said upper end portion of the axle flts therein.

The depth of .the recess is such that when the upper end of the axle is engaging the inner end of said recess, the annular flange 21 of the axle is abutting the face 2| of the hanger (Fig. 1).

For holding each cutter on the axle and also for fastening the axle to the hanger a headed pin it is provided. The pin has its head 2! fitting rather snugly the bottom of the bore 24 of the cutter and has its shank 30 extending upwardly through an axial bore 26' in said axle and through the opening 22 in the hanger. The upper end of the shank is welded at 30' to the outer face of the hanger. The lower end of the axleis reduced at 3| to form an internal annular shoulder 32, and when the cutter is on the axle, this reduced lower end registers with the annular recess 25 in the wall of the bore, the shoulder 32 being opposite the upper end of said recess.

Elongated rollers 33 are located within the raceway produced by the recess 25 and the reduced portion 3| of the axle, whereby the cone cutter is readily rotatable on the axle. The rollers carry the load imposed on the cutter during operation. It is pointed out that the head 29' of the pin 29 is of a larger diameter than the reduced lower end of the axle, whereby said head serves to prevent the rollers from'moving downwardly out of the annular recess 25. The shoulder 32, of course, prevents their upward movement. It is obvious that with the above structure the pin not only serves to secure the cutter to the axle but also fastens said axle to the hanger.

In assembling the device, the cutters and axles are first secured to the hangers of each section. This is accomplished by positioning the head 29 of the pin in the bottom of the bore and then placing the elongated rollers 33 within-the annular recess 25 of the bore. The-axle is then slid down over the shank 30 of the pin, into position within the bore. The upper portion of the shank is then entered into the axial opening 22 in the hanger and welded therein at its upper end.

After each section has been assembled as above, the two sections are then placed around the connecting sleeve l1 and secured together as has been described. The assembling and disassembling is accomplished quickly and easily. There are a minimum of parts and by making the body In in sections, it is not only easier to mount the cutters but manufacturing is simplified. i

It is pointed out that the particular mounting permits the use of the elongated rollers as a bearing surface for the cutters. This is a decided advantage because it is obvious that an increased bearing surface which prolongs the life of the bit and reduces replacements, is provided. Further, the rollers carry the thrust against the cutters during the cutting operation, and it is obvious that this increased surface makes for smoother cutting. Also the provision of the rollers permits the drill to be'eifectively used in drillingin hard formations because of increased strength and durability which is capable of withstanding the increased jar produced by such drilling.

What'I claim. and desire to secure by Letters Patent is:

1. A drill bit including, a pair of complementary members of semi-circular cross section arranged to fit together to form the bit body and having an axial bore when so assembled, semicircular flanges at the upper and lower ends of the sections and arranged to form annular flanges at opposite ends of the axial bore when the sections are fitted together, a connecting sleeve having annular grooved heads at its upper and lower ends for engaging the flanges to hold the sections together, one of said heads being detachable and screw-threaded to the contiguous end portion of said sleeve, a cutter axle at the lower end of each section, and a rotatable cutter on each axle.

2. A drill bit including, a pair of complementary semi-circular sections arranged to fit together to form the bit body and having an axial bore when so assembled, semi-circular flanges at the upper and lower ends of the sections and arranged to form annular flanges when the sections are fitted together, a connecting sleeve having annular grooved heads at its upper and lower ends for engaging the flanges to hold the sections together, acutter axle arranged to be fastened to the lower end of each section, a rotatable cutter arranged to be mounted on each axle, and securing means for said axle and cutter comprising a recess in the body section in which the axle is seated at one end, an annularly shouldered recess in the cutter, a series of rollers in said recess of the cutter, and a securing pin inserted through an axial bore in the axle and an opening provided in said body section, said pin having a headed end portion co-operating with said series of rollers to retain the cutter on the axle and the opposite end portion of said pin being fixedly secured to said body section.

3. In a drill bit of the character described, a

body section, a rotatable cutter, an axle member having an annular flange abutting the face or said body section and an end portion fitte'd in a recess provided therefore in said body section, sa d axle member having a reduced opposite end portion providing a roller race with an annular shoulder, said cutter having an annularly shouldered 'recess therein, a series of rollers in said recess of the cutter and workingupon the reduced portion of said axle-member, and a retaining pin inserted in an axial bore of the axle member and an alined opening provided therefore in the body section, said pin having a head at one end engageable with said rollers, the annular shoulder in the cutter recess being engageable with the opposite ends ofthe rollers, and the opposite end portion of said pin being secured to said body section.

4. In a drill bit of -the character described, a

body section, said' body section having a recess in the face thereof, an axle member having an end portion fittedin said recess and an adja-- cent external annular shoulder abutting. the face of said body section, the outer end portion of said axle member being reduced in diameter with an annular thrust shoulder at the inner end of said reduced portion of the axle member, said axle member having an axial bore and the body section an alined opening, a rotatable cutter having anannularly shouldered recess therein, a series of rollers in said annularly shouldered recess of the cutter and working upon the reduced portion of said axle member, and a retaining pin inserted in the bore of said axle'member and the alined opening of said body section, said pin having a head on one end engaging the adjacent end of the series of rollers in said cutter, the other end of the series of rollers engaging the shoulder on the cutter, and the opposite end portion of said pin being welded to said body section.

FERI A. THAI-IELD.

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