US2879035A

US2879035A - Drilling apparatus

Info

Publication number: US2879035A
Application number: US655559A
Authority: US
Inventors: Carl V Tilden
Original assignee: Individual
Current assignee: Individual
Priority date: 1957-04-29
Filing date: 1957-04-29
Publication date: 1959-03-24
Anticipated expiration: 1976-03-24

Description

March 24, 1959 c. v. TILDEN DRILLING APPARATUS Filed April 29, 1957 FIG. 2.

I N VEN TOR.

' men/5y N f m w A 2 m venient means such as a portable suction cleaner.

DRILLING APPARATUS Carl V. Tilden, Capistrano Beach, Calif.

Application April 29, 1957, Serial No. 655,559

? 7 Claims. 01. 255-50) This invention relates to drilling apparatus for drilling holes in hard rock and the like and more particularly to an improved core drill incorporating simple but effective provision for the removal by air of cuttings.

that these cuttings be flushed away from the base of the bore and it has been common practice to feed water "to the drill head .for the purpose of carrying away the cuttings in the space surrounding the drill barrel. While water is efiective for the purpose a source of pressurized water is not always available. Furthermore, the discharging stream of Water is not readily controlled and, in many instances, the use of water cannot be tolerated as for example where the drilling is to be carried on inside a building or dwelling. Attempts to use air as the flushing medium have also been made but these require the use of motor-driven compressors. Furthermore, large quantities of dust and fine cuttings issuing from the bore are likely to be breathed by the drill operator unless precautions are taken to wear a face mask. Additionally fine dust is deposited about the surrounding area which is objectionable. Suction devices heretofore provided for clearing away the dust and fine cuttings have been unsatisfactory, cumbersome, unreliable, and have interfered objectionally with the operation and manipulation of the drill proper.

These and other serious objections applicable to prior devices are entirely overcome by the present invention which contemplates the provision of a simple core drill readily separable into a few essential components and preferably held together by friction joints. Essentially,

away cuttings in a suction airstream provided by any con- To this end asuction hose connected with the cleaner includes a hood fitting loosely about the shank of the drill and enclosing the exposed outer end of the core barrel, the rim portion ofthe hood being held sealed 'against the rim of a bushing member journaled on the core barrel at the rim of the bore. When the drill is not in operation and the suction source is de-energized all parts of the drill including the suction hood are readily separable. The bushing referred to above serves several important functions including those of centering the drill in the bore, assuring a supply of flushing air to the bore and providing a support for the resilient lip of the suction hood.

Accordingly, it is the primary object of the present invention to provide an improved drill for use in drilling hard brittle materials and incorporating effective and eflicient means for flushing away the drill cuttings to a p collecting receptacle.

i United States Patent ce Patented Mar. 24, 1959 2 Another object of the invention is the provision of an improved core drill having means carried loosely thereon for assuring an air supply into the bore and providing asupport for a readily detachable suction conduit carrying away cuttings.

Another object of the invention is the provision of a core drill having portable suction means for collecting the drill cuttings and including a flexible suction hose held coupled by suction to a bushing journaled about the core drill as long as the suction meansis operating.

These and other more specific objects will appear clearly upon reading the following specification and claims and upon considering in connection therewith the attached drawing to which they relate.

' the drill of this invention features a device for carrying Referring now to the drawing in which 'a preferred embodiment of the invention is illustrated: I

Figure 1 is a view in side elevation of a drilling apparatus incorporating the present invention assembled in readiness for use; and

Figure 2 is a longitudinal sectional view on an enlarged scale through the drill proper.

In Figure 1 there is shown a drilling apparatus designated generally 10 and comprising as major components a portable electric driving motor 11, a drill assembly 12 and a portable source of air suction such as a canistertype suction cleaner 13. The drill head 12 preferably comprises a tubular core barrel 15 provided with tapered ends 16 and .17 having a close frictional fit with a cutting head assembly 18 and an end cap 19. Cutting head assembly 18 includes a ring 20 having a plurality of cutting teeth 21 brazed or otherwise securely fixed thereto. The teeth illustrated are diamond shaped in crosssection andjproject slightly beyond the inner and outer surfaces of ring 20 for the purpose of cutting an annular ring of greater width than the thickness of the cutter head. This assures that the drill will not bind either against the side wall of the bore or against the core extending centrally into the core barrel.

End cap 19 has a flaring inner rim 23 forming a driving friction fit with tapered end 17 of the barrel. Projecting axially from end cap 19 and fixed thereto by threads 25 is a driving shank 24 the outer end of which is shaped to be detachably clamped in a chuck 26 carried by the shaft of the portable driving motor 11. Cap 19 has a number of perforations 27 providing for the passage of a flushing medium as will be described more fully presently.

Looselyjournaled about the exterior of core barrel 15 is a bushing 30 which is longitudinally displaceable on the drill between cutting head 18 and end cap 19, it being understood that the exterior diameters of the cutting head and the end cap are slightly greater than the internal diameter of the bushing. Bushing 30 has a thin-walled cylindrical skirt secured at its outer rim to a radial flange 31. Suitable means, such as ribs 32, project from the surface of flange 31 facing toward the skirt and may extend along the latter to support the bushing in spaced relation to the adjacent wall portions of the material 45 being drilled. Additionally and importantly, these ribs provide flow passages for admitting a flushing fluid downwardly into 'the bore about the exterior of the drill.

The means for flushing away and collecting the cuttings produced by the operation of the drill comprises any simple and suitable suction source conveniently provided by a suction cleaner such as the canister-type generally indicated at 13 in Figure 1. This cleaner comprises a casing; 35 housing a multiple-stage high-suction fan at one end and a filter bag at the other. The removable end cap 36' of the cleaner casing serves to clamp the filter bag in place and to conduct a cutting-laden airstream into the filter bag, the clean air escaping through the bag walls passing into the suction fan from which it is exmay be made of any suitable material, but preferably from soft resilient material such as rubber or plastic. The hood is generally cup shaped and its rim edge may be grooved at 44 to provide a pair of flexible

annular lips

42, 43 having tapering edges formed to seal against the outer surface of bushing flange 31. Groove 44 may contain a soft sponge rubber gasket protruding slightly beyond the rim edges of

lips

42 and 43. As is clearly illustrated in Figure 2, the interior diameter of the suction hood is large enough to fit freely over the end of the drill assembly and to provide a seal with bushing 30 in all operating positions of the drill. Since this may require a suction hood of considerable axial length when using longer core barrels, it is desirable to reinforce the hood against collapse by the pressure difference across its walls. For this purpose the hood may have imbedded therein suitable reinforcing such as wire rings or a wire helix 48.

The operation of the described rock drill apparatus will be apparent from the foregoing description of its simple components. The drill is easily and quickly assembled by pressing end cap 19 and cutting head 18 over

tapered ends

16 and 17 of core barrel 15. Suction hood 39 is then assembled over the end of shank 24 and the latter is clamped within chuck 26 of driving motor 11. Upon completion of the power supply to motor 11 and the closing of switch button 49 for the suction cleaner, both the cutting drill and the suction fan are placed in operation. The cutting head of the core drill may then be pressed against the material to be drilled in the usual manner.

Cuttings produced by drill teeth 21 are picked up by the low-pressure high-velocity airstream entering bore 46 exteriorly of the drill and are carried rearwardly through barrel 15, openings 27, suction hood 39 and flexible hose 37 into the filter bag of suction cleaner 13. In this connection it will be understood that the low suction pressure existing within hose 37 is effective, in cooperation with the exterior atmospheric pressure, to hold hood 39 pressed tightly against flange 31 of bushing 30. Since this bushing is journaled loosely about barrel 15 there is no relative rotary movement between the bushing and suction hood 39. Ribs 32 on the outer surface of the bushing serve to space the latter from the rim edge and side walls of the bore sufficiently to permit an adequate stream of flushing air to flow into the bore about the drill. It will be appreciated that in drilling certain materials larger pieces may be dislodged which will not be entrained by the flushing stream. These may be removed periodically by withdrawing the drill from the bore and clearing such pieces from the core barrel and from the bore. At this time it is convenient to break off the central core formed by the operation of the drill to facilitate further boring.

It will be recognized that core barrel 15 may be of any length depending on the depth of the bore to be drilled. Accordingly, drills of various lengths may be assembled by fitting the cutting head and the end cap to core barrels of different lengths. For this purpose each barrel is provided with identical tapered ends similar to

ends

16 and 17 of the described embodiment.

of the presently preferred embodiments of the invention 4- and that no limitations are intended to the details of construction or design herein shown other than as defined in the appended claims.

I claim:

1. Drilling apparatus adapted for drilling rock-like brittle materials and employing a suction airstream to carry away cuttings therefrom to a place of deposit, said apparatus comprising a core drill having a driving shank, a bushing loosely journaled about said drill and having a flange formed for support in spaced relation to the inlet rim of a bore being drilled, means providing a suction air source independent of the motive means employed to drive said core drill and including a rimmed suction hood communicating with the interior of said drill and having its rim sealed against the flanged end of said bushing whereby the suction airstream flows into the bore being drilled at a point beneath said bushing and picks up cuttings for removal centrally through said core drill and suction hood to a place of deposit.

2. Drilling apparatus as defined in claim 1 wherein said suction hood is cup-shaped and provided with an opening in its bottom fitting loosely about said drill shank.

3. Drilling apparatus as defined in claim 1 wherein said suction hood is cup-shaped with a hole in its bottom loosely fitting said drill shank, said hood having a resilient rim adapted to seal against the surface of said bushing when suction is applied to the interior thereof to provide a stream of flushing air across the cutting teeth of said core drill.

4. Drilling apparatus as defined in claim 1 wherein said suction source comprises a canister-type suction cleaner having a flexible hose connection with the interior of said suction hood, said cleaner being operable to produce a pressure differential across the walls of said suction hood effective to hold the same pressed firmly against the end of said bushing.

5. Core drilling apparatus for drilling brittle materials,

, said apparatus comprising an electric drilling motor having a drill chuck, a core drill having a rod-like shank detachably mountable in said chuck, a tubular core barrel carried by said shank and having a ring provided with cutting teeth across one rim end and being frictionally coupled to the end of said core barrel by means of complemental nesting surfaces, at flanged bushing loosely mounted for sliding movement along said barrel and adapted to fit within the inlet of the bore being drilled, said bushing having provision for admitting a flow of flushing air into the hole about said barrel, a portable suction cleaning means having a flexible hose provided with a suction hood, said hood having an opening fitting about said drill shank and an inlet end shaped to seal against the end of said bushing and to be held there by the operation of said cleaner whereby the cuttings of said drill are carried away in a high velocity suction airstream flowing radially across the cutting teeth and outwardly through said core barrel to a filter depository within said suction cleaner.

6. Core drilling apparatus as defined in claim 5 wherein said suction hood is formed of resilient material reinforced against collapse by wire loops embedded therein.

7. Core drilling apparatus as defined in claim 5 wherein the sealing rim of said suction hood includes a plurality of concentric flexible lips.

References Cited in the file of this patent UNITED STATES PATENTS 1,084,152 Kessel Ian. 13, 1914 2,122,517 Curtis July 5, 1938 2,339,324 Fischer Jan. 18, 1944 FOREIGN PATENTS 3,827 Great Britain Feb. 20, 1908