US 1830625 A
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Description (OCR text may contain errors)
Nov. 3, 1931. 5, w, s o 1,830,625
DRILL FOR OIL AND GAS WELLS Filed Feb. 16, 1927 ATTORNEY Patented Nova? 1931 (moms w. scnaocx, or mnoao,.1nmo
mm. ton on. mass wELLs Application filed Iebr'uary .18, 1927. Serial No. 168,752.
This invention relates to drills and more particularly to cable rock drills used in bormgoil and gas wells.
i A primary object of the invention is to provide a drill of this character having a one ,piece head provided with aplurality of bits or cutters of different types so arranged as to effectively cut across each others path through the rock and so produce a round hole 10 without necessitating the use of other tools,
and which'cutters are adapted to be changed fre uently to provide for drilling a hole of uniiorm' size throughout. 7 Another'object' is to so mount the hits or 16 cutters in the head-that they may be readily .removed by the operator for sharpening or replacing when dulled, thus saving expense vention,
Fig. 2 is a similar view taken in a plane at 80 right angles to Fig.1,
. ig. 3 is a transverse vertical section through the head of the drill with the shank broken off for convenience in, illustration,
Fig. 4 is a bottom plan view of the tool with the bits in place, and
Fig. 5 is a similar view of the head with the bits removed.
In the embodiment illustrated a solid substantially cone-shaped head 1 is shown which merges at its apex into a shank or stem 2 provided at its upper end with a reduced threaded terminal 3 for'connection with the drilling apparatus. A plumb or guide r' 4 is mounted on the upper end of the shan 2 being seated on a shoulder 40 formed at the inner end of a reduced portion 2a ofthe shank. This plumb ring is secured in tion by a set screw' 5 passin radially em ,n through and engaging the each provided with an angular portion 17 to with a plurality of longitudinally extending peripherally spaced sand grooves 6 between which in the head are formed sockets 8 arranged obliquely as shown in Fig. 3 to receive the threaded shanks 14 of the cutters or bits, four of which are here shown and which have said shanks extended-in longitudinal alinement with the bodies of the cutters. A central s0cket7 is larger in size than those and is designed to receive a master cutter 9 which is made in the form of a bull bit, with a reduced threaded rear end for insertion in the socket 7. The sockets 8 are inclined upwardly and inwardly as shown in Fig. 3 so that the bits 10, 11, 12 and 13 which are mounted therein are inclined outwardly at their cutting edges to provide a clearance for the four cutterswhile drilling. This arrangement of the bits 8 and their sockets adapts the cutting strain to beborne by the head 1 and not at the 70 'junctionz giif the bits with the head such as would-be' liable to shear off the bits at this point, These cutters are arranged in pairs, those of each pair being diametrically oppo site each other two of said'cutters being 0111881 cutters and two bull bits. The cutters or bits are held in their sockets by set screws 16 as shown clearly. in Fig. 3 and are preferably receive a wrench for screwing them into and out of the sockets. The two chisel bits 10 and '11 are set opposite each other with cutter edges on two sides of the head and the two bull bits 12 and 13 are set with their cutting corner edges from the center to the outer edge of the drill base on two sides as is shown clearly in Figs. 1 and 4 while the master drill, bit 9 is set with the cutting corner edges to the center of the two chisel bits so that all of the rock. will be cut out since these bits cut across each others paths thereby insuring the formation of a round hole without necessitating the use of any other tools.
The master bit 9 has mounted in the riphery' thereof four screws arranged at 'ametrically zgiposite points so' that the heads 18 thereof 1 thespa'c'es between the master bit and the other bits and said heads are made I K I concave on their outer faces to fit the shanks The outer face of the head 1 is provided of -the cutting. bits as shown at 19 in Fig. i-
2 l f I 1,880,095
These screws 18 which are threaded into the master bit 9 operate to hold thebits 10 '11, 12 and 13 rigidly in cutting osition and t us insure the o eration of the its in unison.
5 From e above description, it will be obvious that this drill has its head and shankconstructed from a single piece whereby strength and durability are, provided and the conesha ed or beveled construction of the head m wi the bit receiving sockets arranged at an incline provide a clearance for the bits while mg. Without further description, it is thought that thefeatures and advantages of the in-,- 15 vention will be readily apparent to those skilledin the art, and itwill, of course, be understood that changes in the form, proportion and minor details of construction may be resorted to, without departing from the 30 spirit of the invention or its scope as claimed.
I claim A multi-bit drill comprising a substantially cone-shaped head having a shank extending from the apex thereof, sand grooves arranged 18 in the outside walls of said head, a central socket opening through the base of the head and surroundedby a plurality of concentrically arran d sockets, the central socket being lar er t an the others, a master drill'bit a6 inserte in said central socket and pairs of chisel and bull bits mounted in the other sockets, these bits being arranged inpairs diametrically opposite each other, and locking elements arranged between said master 35 bit and the ad'acent bits.
. iirEORGE W. SCHROCK.