Tri-cone bit with inserts

July 23, 1963 a. e. ragon 3,098,535

TRI-CONE BIT WITH INSERTS Filed Sept. 23, 1960

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£35

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United States Patent Office

3,098,535

Patented July 23, 1963

3,098,535

TRI CONE BIT WITH INSERTS Austin E. Ragon, Box 682, Rangely, Colo.

Filed Sept. 23, 1960, Ser. No. 58,035

Claim. (Cl. 175—374)

This invention relates to a tri-cone bit, and more particularly to such a bit adapted for straight hole rock drilling.

A primary object of this invention is the provision of an improved bit characterized by teeth or cutters which, in contrast to the conventional bits of this nature, are sharply tapered and pointed.

An additional object of the invention is the provision of such a bit wherein the teeth are spaced as closely as possible, to provide an improved drilling element.

Still other objects reside in the combinations of elements, arrangements of parts, and features of construction.

Still other objects will in part be obvious and in part be pointed out hereinafter and shown in the accompanying drawings wherein there is disclosed a preferred embodiment of this inventive concept.

In the drawings:

FIGURE 1 is a top plan view of one form of bit embodying features of the instant invention.

FIGURE 2 is a sectional view taken substantially along the line 2—2 of FIG. 1 as viewed in the direction indicated by the arrows; and

FIGURE 3 is a bottom plan view of the structure of FIG. 1.

Similar reference characters refer to similar parts throughout the several views of the drawing.

The bit of the instant invention is generally indicated at 10, and comprises three sections, 11, 12, and 13, which are adapted to be fitted together to form a substantially circular bit housing. Sections 11, 12, and 13 fit together to form a circular bore 14, which is centrally positioned, and which may engage the drill shaft, in a known manner. The sections 12 and 13 are substantially identical, and each includes a conical cutter 15, which is mounted on a bearing assembly 16, which is in turn fixedly mounted on a shaft 17 seating in a bore 18 of the housing 12. An additional bearing assembly 16a engages the tip 17α of shaft 17. The conical cutter 15 includes rows 19 and 20 of relatively sharp teeth, positioned, as best shown in FIG. 3, on a series of circumferentially spaced ridges, the ridges being indicated at 19a and 20α, respectively. The ridges 19α and 20α are separated into a series of sharp teeth, as shown, which can be of any desired dimension, but normally ranging from a quarter of an inch to three quarters of an inch long, depending on the bit size, and a quarter of an inch to three eighths of an inch at the base, and terminating in sharp points. Between the rows of teeth 19 and 20 is a space 21, which is adapted for the reception of an adjoining row of teeth on the adjacent conical cutters. The conical cutter of section 13 is indicated in plan in FIG. 3 at 22, is mounted on bearings similar to 16 and 16α (not shown) and is provided with teeth 23 and 24 mounted in rows 23α and 24α, with a space 25 therebetween, the arrangement corresponding to the previously described conical cutter 15.

The third conical cutter 30 is mounted on bearing assemblies 31 and 31a which are carried by a shaft 32 seated in the bore 33 into section 11, and comprises two rows of teeth 34 and 35 which are on ridges 34α and 35α similar to the previously discussed conical cutters. Additional sharply pointed teeth 35b are threadably secured in suitable bores positioned between adjacent ridges 20α, 23α, and 35α. However, the conical cutter 30 is provided with a tip 36, which extends into and fills the space at the intersection of the three conical cutters. Conventionally, such a cutter tip is in the form of a cone or pyramid, however, in the instant invention it is characterized by a series of spikes or teeth 38, which are relatively sharp, and which upon rotation, provide a grinding and chipping action which is not possible with the conventional cone or pyramid.

A space 39 is provided between the rows 34 and 35 of teeth, and is adapted for the reception of the rows of teeth on adjacent cone bits when the device is rotated.

The bit described herein is particularly suited for drilling straight bores in areas having strata which would make straight bore drilling virtually impossible using conventional equipment. Conventional drilling bits will tend to follow the slant of the strata, if slanted strata is encountered and cause the hole to deviate from the vertical.

When the herein described bit 10 is used to drill holes the operation is identical to that in conventional drilling operations. The sets of teeth 19—20, 23—24, 34—35 on conical cutters 15, 22 and 30 respectively, and the teeth 38 on the tip 36 of conical cutter 30 engage the formation during the rotation of the bit 10 to produce a cutting action. However, in the event that slanted strata is encountered, slipping of the bit 10 transverse of the axis thereof is prevented by the circumferentially disposed sharply pointed teeth 35b, whereby the drilling of a straight hole is accomplished.

From the foregoing it will now be seen that there is herein provided an improved tri-cone bit, which accomplishes all the objects of this invention, and others, including many advantages of great practical utility and commercial importance.

As many embodiments may be made of this inventive concept, and as many modifications may be made in the embodiment hereinbefore shown and set forth, it is to be understood that all matter herein is to be interpreted merely as illustrative, and not in a limiting sense.