US1327913A

US1327913A - Rotary boring-drill

Info

Publication number: US1327913A
Application number: US297979A
Authority: US
Inventors: Howard R Hughes
Original assignee: Individual
Current assignee: Individual
Priority date: 1919-05-19
Filing date: 1919-05-19
Publication date: 1920-01-13
Anticipated expiration: 1937-01-13

Description

"I1 Q f g m 1; 4

5 I I I mcjfugfges, mmim H. HUGHES. ROT some DRILL.

APPLICA FILED MAY 19, I919.

1 327, 9 13. Patented Jan. 13, 1920.

mum!!! HOWARDYR. HUGHES, or nous'ron, 'rnxns.

ROTARY BORING-DRILL.

To all whom it may concern:

.Be it known that I, HOWARD R. HUGHES, a citizen of the United States, residing at Houston, Harris county, Texas, have invented a certain new anduseful Improvement in Rotary Boring-Drills, of'which the following is a full, clear, and exact description,

such as Will enable others skilled in the art v to which it appertains to make and'use. the

same.

My invention relates to an improvement in rotary boring drills for use in drilling earth or rock in oil, water, or as wells, or the like. It has special app ication to earth boring drills of the roller type, in which the cutting or drilling operation is performed by means ofrotary cutters adapted -to roll upon the bottom of the hole and disintegrate the material which is adaptedto be flushed away by means of streams of water forced downwardly through the hollow drill stem and the head of the bit. This particular form of roller bit is called the ,cross roller type from the fact that it has twoiside cutters for drilling the outer periphery of the hole and a central cross roller for cutting the center of the bottom of the hole.

' breakingor mutilation thereof. Other ob-' jects and advantages will more clearly ap-- An object of my invention is to provide a pear in the description which follows.

1 Referring to the drawings forming apart of this specification, and in which like characters of reference are applied to like parts throughout the several views, Figure 1 is a side view partlyin elevation and partly in central longitudinal section showing the preferred form of my invention; Fig. 2 is a similar view taken at right angles to the view shown in Fig. 1; Fig. 3 is a bottom plan view of the preferred embodlment; and Fig. 4 is abrokenview of the head of my improved tool, showing a modified mountin of the cross roller cutters.

ily invention is an improvement on the Specification of Letters Patent.

Patented Jan. 13, 1920.

Application filed May 19, 1919. Serial No. 297,979.

type of bit shown in my revious Patent No. 1,174,576, patented Marc 7, 1916. It comprises an approximately cylindrical shaped head 1, having an upper threaded shank 2 for attachment to a rotary drill stem, not

shown. At the 'upper end of the shank 2 is va threaded nipple 3 .of small diameter to which a 'lubricant container is adapted to be attached. The lower face of the head is provided with an approximately V-shaped slot 4 to provide a housing for two sets of cross roller cutters 5. These cutters are mounted upon shafts 6 supported at the center of the bit in a transverse web 7. This web not only furnishes a support for the cutter shafts but also provides a reinforcing means transversely ofthe V-shaped slot 4 to materially strengthen the head of the b1t. This web is an important feature .of

my invention, as will more clearly appear.v

The outer ends of the cutter shafts 6 are supported in downwardly projecting arms 8' from the head, these arms serving to partially close the end of the V-shaped slots 4, in which the cutters are mounted. The cutter shafts 6 are of large diameter at the outer end to accommodate-a cutter 5 of slightly larger diameter than the other cross roller cutters, and is reduced somewhat in diameter toward the center of the head to accommodate a plurality of somewhat smaller cutters 5 The'shaft in my 1m- 7 proved embodiment is inclined somewhat upwardly toward the center of the head and is still further reduced in diameter at 9 and threaded for engagement with the central web 7 of the head. The shaft is retained in position partly by the threaded engagement 9 and a so by means of a locking pin 10 at the outer end of the shaft, this pin being set in the side of the supporting member 8 at right angles to the shaft and fitting within an annular groove 11' in-the periph, cry of the shaft. It will be noted that the threading pf the shaft 6 into engagement with the central web 7 not only assists in retaining the shaft in position but also materially strengthens the head by preventing any tendency of the outer support 8j to'be spread outwardly by the force of the cfuttin action.

The cutter shaft for the cross'ro ers may be horizontal instead of inclined upwardly, as shown in Figs. 2 and 3,'and

obtain astill further strengthening of the head. This form of cutter shaft is shown in Fig. 4. The shaft 6 is mounted at each end in the supporting arm 8 and is; further supported at its central point in the central web 7, as described in the previous modification. The cutters used in this modification are identical with those shown in Fig. 2.

The side cutters 12 are mounted on the sides ,of the head at the lower end thereof. These cutters are disk-shaped, having an outer cylindrical cutting periphery 13 with the outer edge of the cutting face beveled to provide cutting teeth 14 in such position as to act 'upon the side of the hole being drilled. The inner edge of the cutting disk is also toothed, as shown at 15, to accommodate a slightcutting action toward the center of the bit. These two side cutters are mounted upon pins 16 which are made integral with the outer side walls 17 of the V- shaped housing at the lower end of the head. Said pins 16 are threaded and are reduced in diameter at the outer end at 18 to accommodate a locking nut 19.

Threaded upon the pins 16 are bushings 20, these bushings being slightly frustoconical on their outer periphery, as shown in'Fig. 1 The cutters 12 are provided with a frusto-conical inner bearing surface 21 adapted to fit against the bushing 20. The inner faces of the cutters 12 bear against anti-friction washers 22 of ordinary construction. It will be noted that in assembling this cutter the bushing 20 will be inserted within the cutter and in this position will be threaded upon the cutter pin 16. The locking nut 19 will then be threaded upon the cutter end 18 of the pin, thereby serving to prevent the removal of the bushing and cutter. This form of mounting for the cutter is especially adapted for the purpose, in that the upward and outward thrust of the cutting action will be received against the frusto-conical surface of the bushin in such manner as to most efiiclently wit stand the pressure and to provide a bearing surface such that the cutterwill be freely rotatable at all times. The side cutters 12 are so mounted as togive as free rotation thereof as possible, and\for this reason are not housed in the head but are left as open as possible on the sides for free drilling action, the head being recessed slightly at 23 to allow for the inward inclination of the cutters necessary in this form of bit.

The cutters are lubricated by means of lubricant passing downward from the lubricant container through the central channel 24. This channel has two laterally branch ing ducts 25 leading to the center of the cutter shafts 16 and through lateral ducts 26 to the bearing surface between 'the cutter and the bushing. The central channel 24: leads downwardly through the central web 7 to the shaft 6, and through central ducts 27 therein to the bearing surfaces ofthe cutters.

Flushing water for carrying away the material disintegrated by the bit is supplied through vertical channels 28 leading from the upper shank of the bit downwardly to the V-shaped recesses 4. These channels are 4 in number, as shown particularly. in Fig. 3, there being 2 ,of these channels in the housing at each side of the transverse web 7. A large supply of the flushing water is thereby obtained so that the bottom of the hole is washed constantly clean-of cuttings, it being thereby unnecessary to supply flushing water directly upon the side cutters 12.

This form of bit is particularly strong in construction due to the manner in which the cutters are mounted in the head. The strengthening of the two side 'walls 17 by means of a transverse Web prevents any spreading of the lower faces upon which the cutters are mounted and also provides a central support for the cross roller. The forming of the side-cutter pins 16 integral with the head gives an especially strong sup port, and the frusto-conical bushing 20 very effectively takes up. the thrust ofthe cutting action of these cutters. Cutters 5 upon the cross roller shaft 6 are stepped downwardly toward the center of the bit so as to drill a hole with aslightly convex or conical shaped bottom. This will act to prevent a too pronounced whipping or wabbling action of the bit in the hole and will serve to center the bit so that a straight hole may be more readily drilled.

It also allows for a strengthening of the walls 17, upon which the sidecutters 12 are mounted, by making it possible to thicken the walls toward the center of the bit where the cutters are of smaller diameter. The purpose of centering the bit in the hole is further served in the preferred embodiment ofmy bit by inclining the cutter shafts 6 slightly upwardly toward the center. This the cutter is mounted. It is obvious that if it'were necessary to extend the wall of the head downwardly to support the outer end of the cutter pin 16, so as to provide a slot or housing for the outer cutter, it would also be necessary that the outer cutter be of decreasedithickness, and that it also be set farther inwardly toward the center of the head so that the supporting wall at the outer face might extend downwardly to enwill be obvious, what I claim as new and.

desire to'protect by Letters Patent iszi '1. In a rotary boring drill, a head, two sets of cylindrical cross roller cutters so'positioned as to drill a hole. with a conical shaped bottom, two side cutters mounted on pins projecting outwardly from the sides of the head, said cutters being retained in position by frusto-conical shaped bushings threaded .on pins integral with said head,

and locking means to hold said bushings on.

said pins. r

2. In a rotary boring drill, a head, two sets of cross roller cutters thereon, two laterally projecting pins integral with the sides of said head, frusto-conical bushings threaded on said pins, the larger ends of said bushings being toward the outer ends of said pins, and cutters mounted on said v bushings and retained in position thereby.

3. In a rotary boring drill, a head, an'

approximately V -shaped housing in the lower end thereof, a transverse web midway of said housing adapted to divide said housing into two chambers to. strengthen the walls of said housing, inclined cutter shafts in said chamber supportedat one end in said web, cylindrical cutters on said shafts, the cutters being of unequal diameter and arranged with the smaller cutters at the cjenter of the head, two opposite cutters on the,

outer face of the head and means to discharge fius hing water into said housin In testimony whereof, I hereunto a signature this the 15th day of May, A. D.

' HOWARD HUGHES.