US1846177A - Coal drill - Google Patents

Description

Feb. 23,1932. c P. BASCOM ET AL COAL DRILL Filed July 1.6. 1928 E QUE. W m mm drills it was found to be Patented Feb. 23, 1932 UNITED STAT ES PATENT "OFFICE 3 CALVIN P. nAsooM Ann CHARLES woLr, on ST. Lou s, MIssounr COA DRILL Application filed July 16,

This invention relates generally to drills intended for use in mining coal, the predominant object of the invention being to produce a drill by means of which a hole which is of uniform diameter throughout may be drilled in a coal deposit in a coal mine.

The most common method of mining coal involves the use of shells or cartridges containing an explosive, which shells or cartridges are introduced into holes drilled into the body of coal to be mined. The holes referred to are so located with respect to each other that when the shells or cartridges are arranged in said holes, and the explosive in the shells or cartridges exploded, a predetermined section of the wall of coal will be displaced by the explosion and will tumble to the floor of the mine from which it is subsequently removed.

Prior to this invention the holes into which the shells or cartridges were introduced were drilled with the ordinary and well-known coal drills, but due to the construction of these practically impos sible to drill a hole therewith which would be of even approximate uniform diameter throughout. i

The shells or cartridges mentioned are located at the extreme inner endsof the holes and because of the irregular or non-uniform diameter ofthe holes drilled with the drills formerly used it was necessary, after placing the shell or cartridge at the inner end of a hole, to plaster up the entire hole from the shell or cartridge therein to the outer end of the hole with clay. This necessity to plaster up the entire hole was the cause of substantial expense of time and money,inasmuch as the clay and other material tobe used had to be brought into the mine and no little time was consumed in the work of plastering up all of the holes.

In view of these disadvantages encountered in the use of the drills used heretofore, we have devised the drill disclosed herein, which drill is so constructed and arranged that a hole of uniform diameter may be drilled therewith. When a shell or cartridge is fired in a hole which is of uniform diameter 1928. Serial m5. 292,939.

throughouh it has been found that it is entirely unnecessary to plaster up the entire hole from the shell or cartridge to the outer endofthe hole. On the other hand, experiments haveproved that sealthe shell or cartridge in place in the hole by using a ping of clay which is approximately four inches. in length. Thus the use of the drill disclosed herein results in a great saving in time and material, whereby the cost of the mining operation is materially reduced. Figure 1 is a side elevation of our im proved drill, a small portion thereof at the rear of thedrill being shown in section.

Figure 2 is an enlarged section of a fragment of the drill at the head portion thereof. Figure 3 is an end elevation of the head portion of the drill.

Figure iis a cross-section on line 44; of

Figure 2. a

l igure 5 is a perspective of one of the cutting elements'of the drill. a

l igure 6 is a perspective of another of the cutting elements of the drill. a

Figure? is a fragmentary plan View of the rear or tail portion of the drill.

Figure 8 isa View showing a modified form of the'invention.

Referring now to the drawings wherein is shown one embodiment merely of our invention, A designates our Improved drill which comprises generallya head portion B, a shank portion C, and a tail portion D. The shank portion C is made up of a plurality of sections 1, 2, 3, and which are secured together to provide a continuous memher, said sections being tubular in form and each thereof having an internally screwthreaded portion 5 at one end and being provided with an extension 6 at the opposite end of slightly less diameter than the main body of the section, which extension is externally "screw-threaded. To connect together the various sections of which the shank portion C is comprised, the screwthreaded' extensions 6 on said sections are screwed into internally screw-threaded end portionsb of adjacent sections and when this is done a continuous, elongated member is provided. A a a a it is only necessary to secured to saidsections.

of the shank portion 7 tion 10 Each of the sections comprising the shank portion C of ral conveyor '7, each of said sections being provided with a spiral groove 8 (Fig. 2) and the spiral conveyor, which comprises a member substantially L-sh'aped in cross-section is arranged with an edge portion of one leg thereof seated in said spiral groove. 7 The other leg of the L-shaped member extends parallel with the major axis of the shank section, with which it is associated and said member is, of course, arranged spirally about the section. The spiral conveyors on the re-' spective sections making up the shank portion C of the drill and the external and internal screw-threads at the opposite ends of said sections are so made with respect to each other that when adjacent shank sections are properly screwed together, the ends of. the

said adjacent shank secand therefore a complete drill comprised of a pluspiral conveyors on .tions will colncide, shank portion of a ,rality of sections will be provided with a continuous spiral conveyor from one to the other end thereof. The spiral conveyors of the various sections are spot welded or otherwise Each of the sect ons making up the shankportion is provided with a plurality of apertures 9 formed through the wall thereof, through which fine particles of the core which passes through the nterior during the drilling operation may pass. A I Mounted at the forward end of the shank portion C is the head portion of the drill already referred to, said head portion comrising a head 10 having a tubular portion 10 of slightly less diameter thanthe main body portion of the head 10, and which s provided with internal screw-threads (Fig. 2). The internally screw-threaded tubular poris screwed on the externally screwthreaded extension 6 of the forward-most shank section and in this manner the head 10 is secured to the shank portion of the drill.

The head 10 is tubular in form and the annular wall comprising the body portion of said head is provided with a plurality of slots 11 formed therethrough, said slots being approximately radially arranged with respect to p the head and being open at the forward edge of the head while extending rearwardly therein a substantial distance. Also the side walls of each of the slots 11 are approximately parallel with each other and one wall of each slot is provided with an elongated depression 12 formed therein which extends throughout -the slot. The circumferential face of the head is provided with concave portions 13 which are located between pairs of slots 11 as shown in Fig. i'and through the annular wall providing the body portion of thehead openings 14 are formed to permit passage therethrough of fine particles of the core produced during the drilling operation.

the drill is provided with a spi- Arranged in the plurality of slots- 11 formed in the head 10 is a plurality of cutting elements 15, there being one cutting.

element in each slot and each cutting element having a rib 16 formed thereon which is of such shape as to fit into the depression l2v depressions 12. Each cutting element 15 adjacent to its rear end is provided with a notch 17, andwhen the plurality of cutting elements are properly arranged inplace'in the notches 11 of the head 10 the notches 17 of the various cutting'elements willbe alined circumferentially of the head. In like manner, the portions ofthe head 10 located immediately at either side of each of the :slots 11 are provided with notches 17 which coincidewith the notches 17 in the cutting elements. g

18 designates a split friction ring which 'is shaped to closely encircle the head 10; that is to say the friction ring 18 is provided with curved portions which fit closely within the concave portions between the slots 11 of the head and portions 18' joining said curved portions together. 1 To secure the, cutting elements in place in the slots 11 ofthe head the friction ring 18 1s sprung'outwardly and is caused to encircle'the head 10 sothat the portions 18 of said ring are seatedin the notches 17 of the cutting notches and the notches 17 forced in the head. The friction ring is characterized by atendencyto reduce its diameter and. therefore will adhere close- 1y tothe head and because ofthe portions 18 passing through the notchesl'! .and 17 accidental displacement of said cutting elements is prevented. 7,

By referring to Fig. ,3, it will be noted that the cutting noses on entering portions of the cutting elements 15 are located alternately in alinement with the outer and inner faces of the annular wall forming the body portion of the head 10 so that cutting takes place on a pair of circular lines as the drill.v

moves into a body of coal. Also, each cutting element 15' has elongated cutting edges 15 at opposite faces thereof.

Located at the rear, or tail position, of

the shank portion of the drill'i's atail piece 19,

said tail piece havingfan externallyscrewthreaded portion 19 which screws into an internally screwthreaded end portion of an adjacent shank section to secure said tail piece to saidsh'ankportion. The tailrpiece 19 is hollow as shown; in Fig. 1 andthe annular wall thereof is providedwith an opening 20 through which the broken coal comprising'the core which isformedduring the drilling operation may pass from the interior of the drill. The tail piece 19 is provided also with means 21 at its extreme rear end which provides for the attachment of the entire drill to an electrical drilling machine but as this means does not form a part of the present invention, it will not be described in detail herein.

In the use of a drill made in accordance with our invention, said drill is attached toa drilling machine or is operated manually in the usual and well known manner and it has been found that when a hole has been drilled therewith, said hole is of uniform diameter throughout. Gne very important advantage of our improved drill is that the cutting elements are small and may be quickly and conveniently attached and detached from the drill head without special tools, hence a miner may carry a number of these cutting elements into a mine and replace cutting elemcnts being used when same have been dulled in use with sharp cutting elements.

If desired we may arrange the cutting elements 15 at a slight angle with respect to the major axis of the head portionB as shown in Fig. 8. When this arrangement is em ployed, the inclined side faces 15 of the cutting elements during the operation of the drill, will function as conveyors which will move the drillings rearwardly away from the point at which the cutting is being done.

We claim:

1. A coal drill comprising a shank portion, a head at one end of said shank portion, and a plurality of cutting elements individually removably attached to said head, said head comprising a tubular member provided with a plurality of slots extended transversely entirely through the wall of said tubular member in which said cutting elements are arranged, said cutting elements being extended beyond said head in a. forward direction, and the entering portions of said cutting elements being arranged alternately in alineinent with the outer and inner faces of the annular wall comprising said tubular head, an extension on each of said cutting elements seated in a depression formed in a wall of the associated slot, and means comprising a split friction ring which is disposed in apertures formed in the head and in the rear portions of the cutting elements whereby said cutting elements are tired to said head.

2. A coal drill including a shank portion comprising a plurality of shank sections removabiy secured together, spiral members formed on said shank sections, the spiral members in the various shank sections being so arranged that when the plurality of shank sections are secured together to provide the shank portion of the drill, a continuous spiral member will be extended from one to the other end of said shank portion, a head at one end of said shank portion, a plurality of cutting elements removably attached to said head, said head comprising a tubular member rovided with a plurality of slots in whic 1 said cutting elements are arranged, an extension on each of said cutting elements seated in a depression formed in a wall of the associated slot, and means com rising a split friction ring which is dispose in apertures formed in the head and in the rear portions of the cutting elements whereby said cutting elements are fixed to said head.

3. A coal drill including a shank portion comprising a plurality of tubular shank sections removably secured together by means of screwheads formed thereon, spiral members formed on said shank sections, the spiral members in the various shank sections being so arranged that when the plurality of shank sections are secured together to provide the shank portion of the drill, a continuous spiral member will be extended from one to the other end of said shank portion, a head at one end of said shank portion, a plurality of cutting elements removably attached to said head, said head comprising a tubular member provided with a plurality of slots in which said cutting elements are arranged, an extension on each of said cutting elements seated in a depression formed in a Wall of the associated slot, and means comprising a split friction ring which is disposed in apertures formed in the head and in the rear portions of the cutting elements whereby said cutting elements are fixed to said head,

In testimony that we claim the foregoing we hereunto affix our signatures.

CALVIN P. BASGOM. CHARLES WOLF.

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