US1133162A - Drill-bit. - Google Patents

Description

G. W. MGALLISTER.

DRILL BIT.

APPLIGATION FILED JUNE 23, 1913.

Patented Mar. 23, 1915.

F R Z INVENTOR.

DRILL-BIT.

Specification of Letters Patent.

Patented Mar. 23, T9 15.

Application filed June 23. 1913. Seria No. 775,356.

To all whom it may concern:

Be it known that T, GEORGE WATSON Mo- ALLIs'rER, a citizen of the United States, residing at San Francisco, in the county of San Francisco and Statev of California, have invented a new and useful Drill-Bit, of which the following is a specification, in such full and clear terms as will enable those skilled in the art to construct and use the same.

This, invention relates to a rotary drill bit for deep drilling. The bit is intended to operate either in ground where a core is to be produced, or to produce the hole and to break the core as the drilling proceeds,

should that be desired.

An object of. the invention is toproduce a drill bit which will be capable of maintaining a hole of a given diameter for as great a depth as possible in rock'and to furnish as great a length of cutting edges as possible, thus giving the bit a long life.

Another object of the invention is to produce a drill bit which will be in a measure self-sharpening, so that it will not be necessary to remove the drill bit from the hole until .a considerable depth has been drilled, the object being to practically wear out the bit before removing it from the hole.

A further object of the invention is to produce a bit which will have the cutting portions thereof so inclined with respect to the axis and periphery of the bit as to continuously maintain a substantially fixed cutting angle.

Another object of the invention is to produce a bit capable of delivering and discharging the water used in the drilling operations to the cutting edges without forcing the same up the hole outside of the drill and rods, should that be desired.

An embodiment of the invention is shown in the drawings in which the same reference numeral is applied to the same portion throughout, but I am aware that there are many modifications thereof.

Figure 1 is a side elevation of a bit constructed in accordance with this invention, a portion of the bit being broken away for purposes of illustration, Fig. 2 1s a plan view of said bit, Fig. 3 is a vertical sectional view of the bit shown in Fig. 1, Fig. i is a horizontal sectional view of thebit shown in Fig. 1, Fig. 5 is a vertical sectional view of a portion of a bit similar to the one shown in Fig. 1 with suitable core breakers connected therewith, Fig. 6 is a horizontal sectional view of the bit shown in Fig. 5, Fig. 7 is a side elevation of the bit in which the hard segments project beyonl the softer-segments, Fig. 8 is a horizontal sectional view of the bit shown in Fig. 7 as the same would appear without core breakers, and Fig. 9 is a horizontal sectional view of the bit shown in Fig. 7 with the 'core breakers applied thereto I The numeral 1 represents the softer portion of a cylindrical drill rod, said rod being threaded as indicated at 2 and having a cen-' tral opening 3 and two side openings 4:. The numeral 5 indicates spiral segments of a hard steel such as manganese or chrome steel, which segments are connected with the alternating softer spiral segments 6 by a suitable process such as the electrical or 'thermit.

In order to give the drill a start in the be ginning the hard segments are extended down below the soft ones as indicated in Fig. 1 a short distance so that by the time the hard portion has worn awa the softer segments will have received su cient wear to leave them in shape for continuing the cutting operations.

Inasmuch as it is intended to supply and discharge the water used in the drilling operations through the drill itself, the top of the drill is provided with a groove 8 to permit the water from an attached drill rod topass into said outer openings even though the openings in the bit and adjoining drill rod are not accurately alined. It will, of course, be understood that the outer openings 4: are formed in the softer segments of the drill bit.

The bit just described is adaptedfor the production of a core where it is desired to remove the core from the hole without breaking the same. When it is desired to destroy the core as the hole is drilled the bit shown in Figs. 5 and 6 is used. In this form the segments extend spirally around the bit substantially the same as the bit shown in Fig. 1, as indicated at 10 and 11.

The bit shown in Fig. 5 has openings 12 in the soft segments and embedded in others of the soft segments are the core breaking cutters 13 to 18 inclusive. These core breakers are so placed as to gradually scrape off the outer portion of the core, the upper breakers extending nearer the center of the core than the lower ones, so that as the drill passes downwardly it will gradually disintegrate the core formed and permit it to be forced to the surface with the water passing up the central opening.

'In the form of the bit shown in Figs. 7, 8 and 9 spiral segments 19 and 20 are used, the segments 19 extending beyond the segments 20 as far as is deemed necessary to carry on the drilling operations in the given ground, Whether hard or soft. The drill shown is provided with but a single opening and has no core breakers so that a core would be produced thereby and the water used in drilling would pass down inside the drill and up the outside thereof. However, this drill may be equally well used for the purpose of breaking the core and carrying the same to the surface for sampling if desired.

Fig. 9 represents a bit of precisely the same outside appearance as that shown in Fig. 7 but with the hard segments 21 and soft segments 22, two of the soft segments having holes 24 therein while two of the other soft segments have the core breakers 25 embedded therein. In this latter form of the invention the hard segments 21 project bevond the soft segments as much as may be deemed necessary for cutting the given ground.

Having thus described my invention what.

I claim as new and desire to secure by Letters Patent of the United States, is as follows, modifications within the scope of the claims being expressly reserved:

' 1. A bit for rotary drills comprising a rod having means at one end to secure an adjacent drill rod thereto and cutting means at the other end, said rod being formed of a series of alternating hard and soft spiral segments, substantially as described.

2. A drill bit for rotary drills comprising a drill rod having alternately hard and soft spiral segments, said hard spiral segments extending beyond the periphery of the softer segments, substantially as described.

3. A drill bit for rotary drills comprising a rod having means at one end to secure the same to an adjacent drill rod and having cutting means at the other end, said bit being composed of a series of alternately hard and soft segments, the hard segments extending beyond the periphery of the soft segments for their entire length, substantially as described.

4. A bit for rotary drills comprising a rod having an opening therethrough, said rod being threaded at one end and composed nsasaea of a series of spiral alternating hard and soft segments, substantially as described.

5. A bit for rotary drills comprising a rod having a plurality of openings therethrough, one of which openings is central, and said rod being composed of a plurality of longitudinally extending alternating hard and soft segments, substantially as described.

6. A bit for rotary drills comprising a rod having a plurality of openings therethrough, one of which openings is central, said rod being composed of a series of alternately hard and soft spiral segments, and a plurality of core breaking cutters embedded in the softer segments and extending into the central opening, substantially as described.

7. A bit for rotary drills comprising a rod having a plurality of openings therethrough, one of which openings is central, said bit being composed of a series of alternating hard and soft spiral segments, and a series of core breaking cutters embedded in the softer segments and extending toward the center of the central opening through the red, the upper cutters extending nearer to the axis of the drill bit than the lower cutters, substantially as described.

8. A bit for rotary drills comprising a rod having means at one end to secure an adjacent drill rod thereto and having cutting means at the other end, said rod being composed of a series of alternately hard and soft segments, the hard segments extending beyond the periphery of the softer segments, substantially as described.

9. A bit for rotary drills comprising a rod having means at one end to secure an adjacent drill rod thereto and having cutting means at the other end, said rod having a plurality of openings therethrough, one of which openings is central, and being composed of a series of alternately hard and soft segments, the hard segments extending beyond the periphery of the softer segments, and a plurality of cutters embedded in the'soft segments and extending into the central opening toward the axis of the bit, substantially as described.

In testimony whereof I have hereunto set my hand this 10th day of June A. D. 1913, in the presence of the two subscribed witnesses.

GEORGE WATSON MOALLISTER.

Images