US3327794A

US3327794A - Drill bit assembly

Info

Publication number: US3327794A
Application number: US404273A
Authority: US
Inventors: Ernest S Creel
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-10-16
Filing date: 1964-10-16
Publication date: 1967-06-27
Anticipated expiration: 1984-06-27

Description

June 27, 1967 E. s. CREEL DRILL BIT ASSEMBLY 2 Sheets-Sheet 1 fi////x/// Filed Oct. 16, 196

49 F'/G. a

INVENTOR. fie/V557 a 4 ATTOINEYS DRILL BIT ASSEMBLY Filed Oct. 16, 1964 2 Sheets-Sheet 2 INVENTOR.

[EA 57 s, 679554,

United States Patent 3,327,794 DRILL BIT ASSEMBLY Ernest S. Creel, Odessa, Tex. (7621 Beaver Drive, Fort Worth, Tex. 76118) Filed Oct. 16, 1964, Ser. No. 404,273 9 Claims. (Cl. 175-412) This invention relates to the general field of drilling equipment and, more specifically, the present invention relates to improvements in such equipment wherein drill bits having removable cutting blades are utilized in the drilling of a well.

As a general rule, bits of the type to which reference has been made are provided with blades which extend below the bit heads and, by virtue of heavy torque loads which are applied during the drilling operation, the cutting edges of the teeth of the blade are frequently broken or the blades, themselves, bent, whereby it becomes necessary to halt the drilling operation. This is necessarily timeconsuming and expensive.

When it becomes necessary to provide the replacement of the blades it has frequently been found that for mechanical reasons it is very difiicult to separate the drill bit heads from the sub to which they are connected with out still additional loss of time and, additionally, the assembly and disassembly of the blades from the head is cumbersome, unwieldly, and difiicult in carrying out.

Thus, one of the primary objects of this invention is to provide an improved connector means between the drill bit head and the sub which overcome the above objectionable features now found in the prior art while maintaining a safe and positive connection therebetween during the operation thereof.

A further object of this invention is to provide connector or coupling means between the drill bit head and its associated sub which positively locks the blades to the drill head and wherein no special tools are required to effect a disassembly therebetween.

This invention contemplates, as still another object thereof, the provision of connector or coupler means for connecting a drill bit head with a sub wherein the means is non-complex in construction and assembly, comparatively inexpensive to manufacture and maintain, and which is durable and rugged in use.

Other and further objects and advantages of the instant invention will become more evident from .a consideration of the following specification when read in conjunction with the annexed drawings, in which:

FIGURE 1 is a side elevational view of a drill bit embodying the connector or coupling means of the present invention;

FIGURE 2 is a medial cross-sectional view, FIGURE 2 being taken substantially on the vertical plane of line 2-2 of FIGURE 1, looking in the direction of the arrows;

FIGURE 3 is a detail cross-sectional view, FIGURE 3 being taken substantially on the horizontal plane of line 33 of FIGURE 2, looking in the direction of the arrows;

FIGURE 4 is an exploded perspective view showing the details of the connector or coupler means according to this invention;

FIGURE 5 is a vertical cross-sectional view similar to FIGURE 2, but illustrating a second embodiment of this invention; and

FIGURE 6 illustrates, in perspective, a blade utilized in the second embodiment of the invention.

Referring now more specifically to the drawings, reference numeral 10 designates, in general, a hollow elongated substantially tubular sub having an upper end 12 internally threaded as at 14 adapted for connection to the lower end of a drill string (not shown). The opposite or lower end 16 of the sub 10 is formed with external left-hand threads 18 and internal right-hand threads 20.

Reference numeral 22 denotes a drill bit adapted for detachable connection with the lower end of the sub 10. The drill bit 22 includes an enlarged head 24, and an integral axially-aligned elongated hollow cylindrical member 26. The upper or outer end of the cylindrical member 26 is formed with inwardly-extending external threads 28 which extend inwardly to a stop collar 30, and the cylindrical member 26, over that portion thereof extending between the stop collar 30 and the head 24, is reduced in diameter to provide an elongated cylindrical neck 32 and a circumferential shoulder 33. Also formed in the head 24 adjacent the upper end thereof is a downwardly and inwardly-inclined upwardly-facing V-shaped groove 34 having a side thereof opening into the plane of the shoulder 33.

The head 24 is also provided with a plurality of axially and radially-extending circumferentially-spaced slots 35, and the usual axial water or air passage 36 which opens into the cylindrical member 26.

Reference numerals 38 indicate a plurality of identical blades each of which includes a substantially fiat rectangular vertical shank 40 having cutting teeth 42 at the lower end thereof. As is seen in the drawings, the upper inner edge of each blade 38 terminates in an integral arcuate plate 44, the plate 44 tapering in its thickness from its lower edge 45' to its upper edge 45, and the lower inner edge of each shank 40 projects inwardly as at 46. The lower inner edges of each blade 38 terminate in a stabilizing lug 48 of conventional construction.

Reference numeral 50 denotes an elongated substantially hollow cylindrical connector or coupling sleeve internally-threaded at 52 at its upper end, the lower end 54 thereof being reduced in diameter and terminating in a beveled edge 56. The connector or coupling sleeve is formed with a plurality of radially-extending circumferentially-spaced slots 58.which extend upwardly from the lower beveled edge 56 for substantially the axial length of the lower end 54 to give rise to the substantially arcuate flanges 59. The internal diameter of the flanges 59 taper downwardly, as is seen in FIGURE 2, to serve a function to be described.

To assemble the above-described device, the sleeve 50 is first threaded down on the lower end 16 of the sub 10, and it should be remembered that the threads 18 are lefthand and that the threads 52 complement the same. When this threading has been completed, the hollow cylindrical member 26 is partially threaded into the lower end 16, it also being remembered that the threads 20' are right-hand and that the threads 28 compliment the same. This threading continues until the lower end 30' of the stop collar 30 is withdrawn partially behind the flanges 59. The

slots

35, 38 are then brought into alignment with one another and the blades 38 are next assembled. In the embodiment shown in FIGURES 1 to 3, inclusive, the upper edge 45 of the arcuate plate 44 is substantially flush with the upper end 40' of the shank 40. Thus, to seat the blades 38 with the arcuate plates 44 engaging against the neck 32 with portions of the shank 40 seating within the aligned

slots

35, 58 it is necessary to pivot the upper edges 45 over the beveled edges 56 to cause the upper end 49 of each blade 38 to enter its respective slot 58 and then to release the blades 38 so that the lower ends 45 thereof engage and ride on the shoulder 33, and the shanks 40 engage within their respective slots 58 with the ends 46 thereof engaging over the lower end of the head 24.

With the blades 38 in place and with the shanks 40 thereof locking with the sleeve 50 and the head 24, a backing-off of the sleeve 50 will effect relative axial movement of the sleeve 50 toward the head 24 and, vice versa. That is, each will move axially of the sub 10 in equal increments, but in opposite directions. This relative movement continues until the flanges 59 completely embrace the arcuate plates 44 and until the beveled edges 56 thereof engage and lock within the groove 34. The component elements of the device are now in their respective positions as is shown in FIGURES l to 3, inclusive. To disassemble the blades 38 from the device it is only necessary to turn the sleeve 50 in the reverse direction, causing the head 24 and the sleeve 50 to move away from one another and the arcuate plates 44 to become exposed after which the blades 38 may be removed and replaced.

It should here be noted that in reducing the diameter of the cylindrical member 26 to form the neck 32, sulficient clearance is obtained between the neck 32 and the flanges 58 to accept the arcuate plates 44.

The above-described connector or coupling device is shown in conjunction with conventional blades 38. The disclosure was so made in order to show the ready adaptability of the connector or coupling to equipment presently available on the open market. However, the conventional blade is a little troublesome in assembling with the device since, as pointed out above, the arcuate plates 44 must be tipped over the flanges 56 in order to seat the upper ends 40' of the shanks 40 within the slots 58. To overcome this minor difiiculty and to provide still other advantages, the instant invention proposes to utilize in the described connector or coupling device the blades shown in FIG- URES and 6. To utilize the blades shown in FIGURES 5 and 6, the coupler device must be altered in but a minor respect.

Since the coupling devices of both embodiments of the invention are substantially identical, and the same is also true with respect to the blades, the same reference numerals will be employed, increased by 100 to diiferentiate elements of the second embodiment of the invention from their counterparts found in the first embodiment thereof. Thus, and referring to FIGURE 5 of the drawings, the only change in the construction of the coupling device resides in the formation of a circumferential groove 200 in the neck 132, the groove 200 being adjacent to but spaced from the stop collar 130.

Referring now specifically to FIGURE 6, it will be noted that the arcuate plate 144 has been shifted downwardly on the inner edge of the shank 140 to provide a clearance 300 between the upper end 145 thereof and the upper end 140 of the shank 140. Additionally, the plate 144 is provided with an arcuately-shaped rib 302 that projects laterally from the concave side of the arcuate plate 144, the rib 302 being substantially parallel to the upper and lower ends 145, 145' of the plate 144, and being adjacent to but spaced below the end 145.

To assemble the blades 138' with the coupling device it is no longer necessary to tilt the blades in the manner described above since the clearance required through the use of the blade 38 due to the presence of the upper edge 145 substantially flush with the upper end 40 of the shank 40 is obviated. This clearance is clearly shown in FIG URE 2 wherein appreciable space is seen to exist between the upper end 45 of each blade 38 and the inner end of its associated slot 58. Thus, the arcuate plates 144 may be fit flush against the neck 132 with the upper end of each blade 140 fitting against the inner end of each of its respective slots 58 as is shown in FIGURE 5. The rib 302, of course, enters the circumferential groove 200. The blade 138 is constructed of such vertical length that the end 145' will seat against the shoulder 133 when the rib 302 is engaged within the groove 200. The taper on the blades 144 taken in conjunction with the taper on the flanges 59 cooperate to normally hold the end 140' out of engagement with the inner end of the slot 58. This is necessary since the sleeve 50 must be permitted to travel in order to keep the blades tight as the component elements of the invention wear.

In all other respects, the two embodiments of this invention are identical.

Having described and illustrated a plurality of embodiments of this invention, it will be understood that the same are offered merely by way of example, and that this invention is to be limited only by the scope of the appended claims.

What is claimed is:

1. An article of manufacture comprising a drill bit, said drill bit including an elongated substantially hollow cylindrical member having an enlarged head at one end thereof, said enlarged head having a plurality of circumferentially spaced axially extending blade receiving slots formed therein, said slots extending inwardly from the outer peripheral side of said enlarged head, the other end of said cylindrical member having threads formed thereon terminating in spaced relation relative to said head, said threaded other end providing means for connection to a sub, that portion of said cylindrical member extending between said head and said threads being necked down, and a stop collar on said cylindrical member between said neck and said threads.

2. A coupling device for connecting a drill bit having a drill head with a drill string, said coupling device including an elongated substantially hollow sub, first means on said sub movable axially thereof toward and away from said sub, second means connecting said drill bit in said sub to move said head axially toward and away from said sub, said first and second means being operable to simultaneously move said first means and said head toward and away from one another, and third means connecting said first means with said second means.

3. A drill bit assembly including an elongated substantially hollow tubular sub, means on one end of said sub for connection with a drill string, the other end of said sub having internal and external threads of, respectively, opposite hand, an elongated substantially hollow internally-threaded cylindrical sleeve having an end thereof threadedly engaging said external threads of said sub for movement axially thereof, the other end of said sleeve projecting axially beyond said other end of said sub, a drill bit comprising an elongated substantially hollow cylindrical member having an enlarged head at one of its ends, the other end of said cylindrical member being externally threaded for engagement with said internal threads of said sub, and means connecting said sleeve with said head whereby rotation of said sleeve in one direction or the other elfects simultaneous axial movement of said sleeve and drill bit toward or away from one another.

4. A drill 'bit assembly for detachably connecting drilling blades with a drill stem, said assembly including an elongated substantially hollow tubular sub, means on one end of said sub for connection with a drill string, the other end of said sub having internal and external threads formed thereon of, respectively, opposite hand, an elongated substantially hollow cylindrical sleeve having a pair of opposed open ends, said sleeve being internally threaded for threaded engagement with said external threads of said sub whereby said sleeve may be moved axially toward and away from said sub, the other end of said sleeve projecting beyond the other end of said sub, a drill bit comprising an elongated substantially hollow cylindrical member having an enlarged head at one of its ends, the other end of said cylindrical member being externally-threaded for threaded engagement with said internal threads of said sub whereby said drill bit may be moved axially toward and away from said sub, and means on said sleeve and said head to receive the opposed ends of said blades whereby rotation of said sleeve in one direction or the other causes said sleeve and said head to move axially of said sub, simultaneously, toward or away from one another.

5. A drill bit assembly as defined in claim 4, wherein said blades each includes a shank and wherein said sleeve and said head are each provided with pairs of aligned slots to receive said shanks therein wherein rotation of said sleeve in one direction will cause said drill bit to rotate in the same direction to cause engagement of said other end of said sleeve with said head.

6. A drill bit assembly as defined in claim 6, wherein each of said blades is provided with an arcuate plate adapted to engage against said cylindrical member adjacent said head, and said sleeve upon rotation thereof moves axially of said sub to cause said other end of said sleeve to embrace said arcuate plates and to engage against said head.

7. A drill bit assembly as defined in claim 6, wherein said external threads on said hollow cylindrical member terminate in spaced relation relative to said head, and that portion of said cylindrical member between said external threads and said head being reduced in diameter to form a neck to receive said arcuate plates thereon.

8. A drill bit assembly as defined in claim 7, wherein said other end of said sleeve is beveled, and the adjacent end of said head is provided with a V-shaped groove to lockingly receive said beveled end therein.

9. A drill bit assembly as defined in claim 8, wherein said neck is provided with a circumferential groove and said plates are each provided with an arcuately-shaped rib for engagement Within said groove.

References Cited UNITED STATES PATENTS CHARLES E. OCONNELL, Primary Examiner. N. C. BYERS, Assistant Examiner.

Claims

4. A DRILL BIT ASSEMBLY FOR DETACHABLY CONNECTING DRILLING BLADES WITH A DRILL STEM, SAID ASSEMBLY INCLUDING AN ELONGATED SUBSTANTIALLY HOLLOW TUBULAR SUB, MEANS ON ONE END OF SAID SUB FOR CONNECTION WITH A DRILL STRING, THE OTHER END OF SAID SUB HAVING INTERNAL AND EXTERNAL THREADS FORMED THEREON OF, RESPECTIVELY, OPPOSITE HAND, AN ELONGATED SUBSTANTIALLY HOLLOW CYCLINDRICAL SLEEVE HAVING A PAIR OF OPPOSED OPEN ENDS, SAID SLEEVE BEING INTERNALLY THREADED FOR THREADED ENGAGEMENT WITH SAID EXTERNAL THREADS OF SAID SUB WHEREBY SAID SLEEVE MAY BE MOVED AXIALLY TOWARD AND AWAY FROM SAID SUB, THE OTHER END OF SAID SLEEVE PROJECTING BEYOND THE OTHER END OF SAID SUB, A DRILL BIT COMPRISING AN ELONGATED SUBSTANTIALLY HOLLOW CYLINDRICAL MEMBER HAVING AN ENLARGE HEAD AT ONE OF ITS ENDS, THE OTHER END OF SAID CYLINDRICAL MEMBER BEING EXTERNALLY-THREADED FOR THREADED ENGAGEMENT WITH SAID INTERNAL THREADS OF SAID SUB WHERE SAID DRILL BIT MAY BE MOVED AXIALLY TOWARD