US2598518A

US2598518A - Rock bit

Info

Publication number: US2598518A
Application number: US22350A
Authority: US
Inventors: Normand E Dufilho
Original assignee: Individual
Current assignee: Individual
Priority date: 1948-04-21
Filing date: 1948-04-21
Publication date: 1952-05-27
Anticipated expiration: 1969-05-27

Description

Patented May 27, 1952 UNITED STATES PATENT'OFFICE- ROCK BIT Normand E. Dufilho, Longview, Tex.

Application April 21, 1948, Serial No. 22,350

3 Claims. (01. 255-71) This invention relates to drill bits of the type used for rock and hard formations wherein the cutting action is accomplished through crushing or chipping, and in particular a rock drill having a rotary cutter head positioned to rotate about an axis at an acute angle to the axis of the drill body whereby the teeth of the bit head are set down in rotation order as with a walking effect and without circular slippage.

The purpose of this invention is to provide an improved drill bit for driling wells for oil, gas, water, and the like wherein the teeth of a rotary cutter head advance step by step whereby cutting is accomplished by a crushing and chipping action.

The usual bits for drilling wells and the like are designed to operate on various mechanical principles such as the drag bit which cuts or removes the material or formation in its path by scraping with one or more blades, and the rock bit which was intended primarily for formations too hard to be cut by the drag bit and which consists of toothed cones or wheels which attack the formation with a crushing action, but because of the hard service to which these bits are put the useful life thereof is relatively short. With this thought in mind this invention contemplates a drill bit having a rotating body with a cutter head rotatably mounted thereon and positioned at a slight angle to the body wherein roller bearings are provided between the cutter head and body to take the thrust and a centrally disposed passage is provided through the body providing a drilling mud passage for carrying 01f cuttings which flow upward outside of the bit.

The object of this invention is, therefore, to provide an improved drill bit for drilling rock and other hard formations with a crushing and chipping action.

Another object of the invention is to provide an improved drill bit having a rotary cutter head in which roller bearings are used to take the thrust.

Another object of the invention is to provide a drill bit which operates with a step by step actlon providing a rotary crushing or chipping effect as it operates.

A further object of the invention is to provide an improved rock drill having a rotating body with a cutter head rotatably carried thereon which is of a simple and economical construction With these and other objects and advantages in view the invention consists of the new and useful combination. construction, and arrangement of parts as hereinafter more fully described,

set forth in the claims appended hereto and disclosed in the accompanying drawings forming part hereof, wherein:

Figure 1 is a view showing a side elevation of the drill head with part broken away showing a vertical section through the cutter head thereof and illustrating the drill in an opening.

Figure 2 is a view looking upward toward the under surface of the cutter head showing the teeth, and taken on line 22 of Figure 1.

Figure 3 is a cross section through the drill body taken on line 3-3 of Figure 1.

Figure 4 is a section between the drill body and cutterhead taken on line 44 of Figure 1.

Referring now to the drawings wherein like reference characters denote corresponding parts the improved rock drill of this invention includes a drill body l0 and a cutter head I l which is rotatably mounted an on angularly disposed spindle l2 of the body.

The drill body is cylindrical and a tapering threaded shank I3 is provided at the upper end by which it may be attached to a drill rod. The intermediate portion of the drill body is provided with substantially semi-circular recesses M in whichrollers 15 with pins [6 extending from the ends thereof are positioned. These rollers contact the wall surfaces of the well and take the lateral thrust holding the drill centered in the well.

The spindle l2 extends from an inclined surface l'l, to which it is perpendicular, and the axis of the spindle intersects the axis of the drill body at the point I8, the axis of the spindle and cutter head being at an acute angle to the axis ofthe drill body. The spindle I2 is provided with an annular recess l9 which registers l with a similar recess 2!! in an opening 2| in the cutter head, and balls are positioned in the recesses, as indicated by the numeral 22. The end of the spindle is provided with a collar 23 having an annular recess 24 therein in which a sealing ring 25, extending from a similar recess 26 in the cutter head, is positioned to insulate the bearing areas from dirt, grit, and the like. Radially disposed roller bearings 21 are positioned around the collar 23 which bear against the end of the spindle and inner surface 28 of the cutter head. A gasket 29 is also provided between the end of the body or surface I! and the inner end of the cutter head to further seal and protect the bearings.

The outer surface 30 of the cutter head II is positioned thereon, and as illustrated in Figure l, the angle between the axis of the cutter head and drill body is determined in relation to the cutting face of the cutter head so that the teeth on one side of the center of the cutter head will be positioned perpendicular to the axis of the drill body, and as the drill body is rotated the teeth will advance, step by step, cutting the rock with a chipping and crushing action.

The center of thecutter head ll is provided with an opening 32 which communicates with a centrally disposed opening 33 in the drill body providing a drilling mud passage for carrying 01f cuttings which flow upward outside of the bit.

It will be understood that modifications .may be made in the design and arrangement of the parts without departing from the spirit of the invention.

What is claimed is:

.1. .In a rotary rock drill bit, the combination which comprises a cylindricaldrill body having an inclined surface on the lower end with a spindle extended from the said inclined surface and with the spindle positioned whereby the axis thereof "is perpendicular to the said inclined surface andintersects the longitudinal axis of the drill body at a point spaced from the said inclined :surface, the lower end of said spindle having a. conical surface and the lower side of said conical surface being perpendicular to the axis of said drill body, and a drill headhaving conical shaped inner and outer surfaces journaled on the spindle and positioned with the conical shaped inner surface coacting with the conical shaped end surface of the spindle and having concentric rows of radially disposed cutting teeth extended outwardly from the said outer conical shaped surface thereof, said drill body having bearing surfaces on the outer surface thereof and the periphery of said drill head being aligned with the said bearing surfaces of the'drill body.

2. In a rotary rock drill bit, the combination which comprises-a cylindrical drill body having an inclined surface on the lower end with a spindle extended from the said inclined surface and with the spindle positioned whereby the axis thereof is perpendicular to the said inclined surface and intersects the longitudinal axis of the drill body at a point spaced from the said inclined surface, the lower end of said spindle having a conical surface and the lower side of said conical surface being perpendicular to the axis of said drill body, and a-drill head having conical shaped inner and outer surfaces journaled on the spindle and positioned with the conical shaped inner :surfacecoacting with the conical shaped end surface of the spindle and having concentric rows of radially disposed cutting teeth extended outwardly from the said outer conical shaped surface thereof, said teeth being staggered and having radially disposed open mud escape channels between the teeth, said drill body anddrill headhaving a vertically 4 positioned centrally disposed passage extended from the face of the drill head upwardly through the drill body providing a mud passage, said drill head having an inner end surface positioned perpendicular to the axis of the said spindle upon which the drill head is positioned and extended to contact the said inclined surface on the lower end of the drill body, said end surface of the drill head and inclined surface of thedrill body coacting with the conical shaped surface at the end of the-spindle to provide increased bearing surfaces for withstanding the excessive load resulting from operation of the drill bit.

3. In a rotary rock drill bit, the combination which comprises a cylindrical drill body having an inclined surface on the lower end with a spindle extended from the said inclined surface and with the spindle positioned whereby the axis thereof is perpendicular to the said inclined surface and intersects the longitudinal axis of the drill body at a point spaced from the said inclined surface, thelower end of said spindle having a conical surface and the lower side of saidconical surface being perpendicular to the axis of said drill body, a drill head having conical shaped inner and outer surfaces journaled on the spindle and positioned with the conical shaped inner surface coacting with the conical shaped end surface of the spindle and having concentric rows of radially disposed cutting teeth extended outwardly from the said outer conical shaped surface thereof, said teeth being staggered and having radially disposed open mud escape channels between the teeth. radially disposed roller bearings positioned between the inner conical shaped surface of the head and end surface of the spindle, and spaced longitudinally positioned bearing rollers .journaled inthe outer peripheral surface of the drill body and positioned with the outer surfaces thereof parallel to the outer surface-and axis of the said drill body.

NORMAND E. DUFILHO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS