Drill Head Unit With Throwaway Insert Holders

Abstract

A drilling tool for use in the mining industries, the present tool having advantages over presently existing drill heads in view that it costs less, provides more cutting edges and promotes safety to miners, the device consisting of a main member having a shank for being attached to a drilling machine or some other device, the main member at its opposite end having a working head that includes securement there to of a pair of throw away insert holders, each one of the holders having a hexagonal shaped carbide throw insert secured there to by means of a screw.

Description

This invention relates generally to mining industry tools. More specifically it relates to drill heads.

A principal object of the present invention is to provide a drill head unit having important advantages over conventional drill heads used in the mining industry, one of the advantages comprising a saving of approximately 50%. At the present time a good drill head used in a mining operation may cost approximately six or eight dollars, whereas the present invention can be sold at not more than four dollars in comparison.

Another purpose of the present invention is to provide a drill head unit having the advantage over existing drill heads by including from three to six cutting edges.

Still another object of the present invention is to provide a drill head unit wherein the cutting edges can be quickly and easily repositioned by turning a single screw.

Still another purpose of the present invention is to provide a drill head unit which accordingly is superior to a presently existing drill head and which has been proven in actual use in the field and which has been phrased by mining operator's as being superior.

In the present mining industry, a drill head is made of a single solid piece, the drill head having two prongs with carbide brazed upon them, and when in use, the carbide wears or breaks so that the tool must necessarily be resharpened and the process repeated until the carbide is used up or thrown away. Then the entire tool is thrown away. In the present invention, a main member and a pair of supporting holders are retained and only individual carbide throw away inserts are discarded after three to six sides thereof have been utilized.

Still another purpose is to provide a drill head unit which serves a dual purpose; the main member being used in clockwise or counter-clockwise manner. The insert holders are changable from one side to another, and they are interchangeable from one size tool holder to a larger or smaller size tool holder.

Other objects of the present invention are to provide a drill head tool holder which is simple in design, inexpensive to manufacture, rugged in construction, easy to use and efficient in operation.

These and other objects will be readily evident upon a study of the following specification and the accompanying drawings wherein:

FIG. 1 is a side elevation view of the present invention shown assembled.

FIG. 2 is a perspective view of the main member.

FIG. 3 is a bottom perspective view thereof.

FIG. 4 is a side elevation view of the insert holder.

FIG. 5 is a top view of the main member.

FIG. 6 is a cross sectional view of the device taken on line 6--6 of FIG. 8.

FIG. 7 is a detail view of the interfit of the parts.

FIG. 8 is a front elevation view of the invention shown assembled.

Referring now to the drawings in detail, the reference numeral 10 represents a drill head unit holder according to the present invention wherein there is a main member 11 which at one end thereof is integral with a longitudinally extending square shank 12 which is 1/2 inch in square dimension. A transverse extending threaded hole 13 extends near the terminal end of the shank 12 and another opening 14 extends longitudinally through the shank and the entire main member and is used for liquid coolent flowing to the cutting head and the cutting edges to be described herein after.

A working head 15 on an opposite end of the main member includes a pair of three eighth of an inch diameter openings 16 which extend at a 5.degree. angular pitch respective to a longitudinal axis of the main member 11.

Within each of the openings 16 there is insertable a shank 17 of a throw away insert holder 18, the shank 17 having a notch 19 for receiving a set screw 20 threadingly engaged on opposite sides of the working head 15.

Each of the two throw away insert holders supports a hexagonal carbide throw away insert 21 secured there to by means of a screw 22 threadingly engageable within a threaded opening 23 in the holder 18. As shown in FIG. 7, it is to be noted that the holder 18 includes a flat side 24 against which the throw away insert 21 is positioned and the holder includes a V-shaped notch 25 of 120 degrees angle and into which one corner 26 of the throw away insert 21 is placeable. Thus the insert 21 is in a fixed and secured position so it cannot move. For this reason it is to be noted that the side edges of the insert 21 are angularly inclined and the angular side of the holder notch 25 is correspondingly inclined so that as shown in FIG. 6, the inclined edges abutt with each other.

As best shown in FIG. 8, it is to be noted that the inserts are located facing in opposite directions so that during rotation of the main member, the inserts are located 180.degree. apart during rotation of the tool.

The throw away insert 21 is three quarters of an inch wide, three sixteenths of an inch in thickness and has a three sixteenth of an inch diameter central opening 27 so to receive screw 22.

It is to be noted that the one sixteenth of an inch diameter opening 14 extending longitudinally through the main member 11 serves to bring coolent liquid to the cutting edges so that the cutting edges of the insert do not get hot but remain cool. It is well known that if a hot drill head used in mining operation hits a gas pocket in the ground while drilling, there may be an explosion. With the coolent thus being supplied through opening 14, the cutter edges remain cool so to prevent a dangerous explosion, thereby promoting mining safety.

Thus there is provided a drill head tool holder with inserts that is superior to existing drill heads used in the mining industry. The present invention consists of only the three parts plus the inserts each one of which has six cutting edges so that it can be used for an extended life and after it is used up then only the insert is thrown away and not the entire tool such as is presently being done by conventional drill heads.

The insert holders with inserts are designed to cut clockwise or counter-clockwise. For instance, if a person has two tool holders in operation, one turning in a clockwise direction, and the other turning in a counter-clockwise direction, the inserts can be used in one holder; and if needed immediately, they can be taken out of the one and interchanged with the other. This feature is particularly important in view that at the present time in drilling operations conducted in the mines, two different size holes are drilled. To drill these two holes, the mine operator must use three different size drill heads; one size for the coal and two different sizes for the roof.

The advantage of the present tool is this: It uses two different size holders, one for the coal and one for the roof. The insert holder with inserts serves a dual purpose. It uses two inserts in the holder for the coal. Then interchange the same to insert holders with the tool holder in the roof. The difference in this: By using the present holders and insert holders with inserts, two drill heads are eliminated.

Thus the main member being the tool holder, can be used in different sizes, the insert holders with inserts being changeable and interchangeable serving a dual purpose.

Claims

What I now claim is:

1. A drill head unit comprising in combination:

a. a main member,

b. a shank integrally formed with the main member at one end thereof,

c. a working head disposed on the other end of the main member, the head having at least a pair of openings formed therethrough,

d. at least a pair of holders, the holders being insertable into the openings, and

e. at least a pair of inserts each being supportable by one of the holders, and

wherein the shank has an aperture formed therein and extending through the holders.

2. A combination as set forth in claim 1 wherein the openings have a 5.degree. angular pitch respective to a longitudinal axis of said main body member, said angularly inclined openings each supporting one of said holders.

3. The combination as set forth in claim 2, wherein said holder includes a longitudinal shank receivable within said angularly inclined opening of said member, and which further includes means for securing the shank in the opening, an opposite end of said holder having a seat formed thereupon into which said insert is placeable, said seat including a flat face and a V-shaped edge to form a corner into which one corner of the insert is receivable.

4. The combination as set forth in claim 3 including means for securing the insert to the holder and wherein said insert comprises a flat member having six hexagonal side cutting edges.

5. The combination as set forth in claim 3 wherein said insert comprises a flat member having six hexagonal side cutting edges, said insert being securable to said holder by means of a single screw.

6. In an improved drill head unit, the combination of a main member supporting a pair of holders, an extending square shank formed integrally with the main body member at one end thereof, the shank having at one end a threaded aperture extending through the holder, the opposite end of said main member forming a working head, said working head being provided with a pair of openings at a 5.degree. angular pitch respective to a longitudinal axis of said main body member, said angularly inclined openings each supporting one of said holders, and each of said holders supporting a hexagonal carbide throw away insert.

7. The combination as set forth in claim 6 wherein said holder includes a longitudinal shank receivable within said angularly inclined openings of said main member and is securable therein by means of a set screw positioned against a notch in said holder shank, an opposite end of said holder having a seat formed thereupon into which said insert is placable, said seat including a flat face and V-shaped edge to form a corner into which one corner of said hexagonal insert is receivable.