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Publication numberUS274740 A
Publication typeGrant
Publication dateMar 27, 1883
Filing dateDec 2, 1882
Publication numberUS 274740 A, US 274740A, US-A-274740, US274740 A, US274740A
InventorsSamuel W. Douglass
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
douglass
US 274740 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

0,0.. 2 1 VU., u

2 Sheets- Sheet 1.

Patented-Mar.27,1883.

(No Model.)

R S.. W. DOUGLASS.

EXPANSION ROTARY DRILL. IAT-0.274340.

(No Model.) 2 Sheets-Sheet 2.

S.`W. DoUGLAss. EXPANSION ROTARY DRILL.

No. 274.740. Patented Mar. 27,188.3.

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UNITED STATES PATENT Ormea.

SAMUEL W. DOUGLASS, OF NEW YORK, N. Y., ASSIGNOR TO THE AMERICAN DIAMONDBDCK BORING COMPANY, OF SAME PLACE.

EXPANSION ROTARY DRILL.

SPECIFICATION forming part of Letters Patent No. 274,740, dated March 1883.

Application tiled December 2, 1882.

To all whom it may concern.-

' Be it known that I, SAMUEL W. DoUGLAss, ofthe city of New York, county and State of New York, have invented a new and useful "Improvement in Expansion Rotary Drills, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, in which like letters indicate like parts. p

Figure 1 is a longitudinal section of the expansion drill, showing l the cutting-bars extended. Fig. 2 is the same with the cuttingbars retracted. Fig. 3 is across-section through which water is forced to keep the drill clear;

but l do not limlt myself to such drills, as my invention can, also be used on any rotary expansion-drill. It frequently happens that it is desirable to enlarge the hole cut by the apparatus at some particular place below the l surface, and this invention affords a means for so doing superior, as I believe, to any heretofore known.

In the following description I will assume `that the boring apparatus is in a vertical position.

A is the lowermost portion of my expansiondrill, and it is a metallic head, preferably steel,

of the shape shown iuvertical section in Figs.

lb and 2 and in cross-section in Fig. 5 5 but at its upper part, at 1, it is cylindrical, and it may be cylindrical throughout, if preferred.

B is a coupling, also cylindrical, and of the same external diameter as A.

C is the uppermost section of my expansiondrill, and its lower part serves as a portion of the cylinder for the piston H, as hereinafter set forth. The section O is cylindrical, and of the saine external diameter as both the coupling B and the head A. The couplingB is preferably connected With the section O by screwthreads 2, and with the head A by screwthreads 3 5 but, if preferred, it may be made in one piece with either of the other pieces. These three parts A, B, and G constitute the (No model.)

case of my improved drill, or that which, in the claims, I call the drilL t D and D' are an extension of the piston-rod proper, and D has upon the whole or part of it heavy screw-threads, by which itis connected with the drill-rod. The drill-rod is not shown.

E is the piston-rod proper, which passes through the cylinder-head Gr, and has the piston H fastened to it. t f Y v F is a circular piece of metal, square at top and bottom, and it fits tightly into the upper end of the section C, and is keyed to it by the keys N, which enter half and half into the msection O and into this circular piece of metal,

thereby preventing the same from turning in the section O. There is a square hole through this piece F, through which passes the square section of the extended piston rod, (shown at D.)

G is a cylindrical piece of metal, which is rigidly fastened in the section O by the screwthreads 5, and it serves as the head for the piston-cylinder'. The threads 5 are cut on an inwardly-projecting circumferential portion of the section O, (shown at O.) Through the cylinder-head Gr the piston E works, as before stated,and it is provided with the usual packing-box used in such cases, (seen at 6.)

H is the piston, which is firmly attached to the piston-rod E, and it is provided, if desired, with the usual packing, 7.

I is a at ring, of metal, rigidly fastened to the piston-rod D at the top of the square portion D' thereof, and its diameter is not greater than the outside diameter of the section O. It has recesses on its under side forthe accommodation of the heads Aof the keys N, if they have heads.

J are strong pivoted cutting-bars, made of steel. They are preferably four in number, and square in shape, except at the lower end, and are pivoted at or near their lower ends to the headA by the pins L. The shape of the head A, for the accommodation and convenient insertion of these bars and pins, is best seen in seotionin Fig. 5. These cutting-bars are armed with diamonds on their outer face, as usual, or other cutting devices, if desired, and they lie in recesses cutfor them within the head A, (seen atS.) These recesses are of suicient size rO-M and conform to the shape ot' these bars, so that the bars can be completely retracted within them.

K are toggle-arms, which are pivoted at one end to the upper end of the cutting-bars by the pins m, and at their other end to the piston-rod Eby the pins n. A portion ofthe head A is cutaway, as at 9, to allow oi' the swinging of these toggle-arms, and they are so piv: oted to the piston-rod that when the cuttingbars are projected the toggle-arms shall liesubstantially at right angles to the piston-rod. The piston-rod is also cut away, as at 9', to allow the toggle-arms to swing in it. The piston-l rod may be made in two sections, as shown in the drawings-one (the lower one) shown by E, and the other (the upper one) shown byD D and they are connected and made one conti nuous rod by the screw-threads 10. For the purpose of supporting, guiding, and giving greater strength to the piston-rod, the lower portion of E, as seen at 1l, works into a recess made for itin the head A, and this portionll may be either round or square, prelerably square, the recess in which it enters being made to correspond, for it then aids in turning the drill,'as hereinafter setforth. The pistonrod E is cut away in triangulanshaped spaces, (seen at 12,) to allow the pins n to be easily put in place and fastened.

Around the lower end ofthe cutting-bars a' water channel or passage-way (seen at 13) is cut out of the head A. Through this channel or passage the water can pass; audit can also pass between the cutting-bars and the walls ot' the recesses, in which they work. Through the extended pistonfrod D D', and also through that portion of it marked E, which is above the piston H, a water-passage is out, (shown at 14 and clearly seen in Fig. 3.) Just at the upper side of the'piston Hthis water-passage divides into a number of smaller passages, (seen at 15.) These may, as shown, run at right angles to the passage 14, and they dischargejust above the piston H and between it and the head G; and in order that there may be a space between the piston and the head, so that the water may have an opportunity to eX- ert its force, I extend the inwardly-projecting circumferential portion of the section (seen at O) somewhat below the under side of the cylinder-head G, which thus presents a shoulder, O', against which the piston brings up and cannot go any farther; and the adjustment ot'.

vthe parts should be such that the piston will not strike this shoulder until the cuttiug-arms vJ have beenrfully retracted and the diamonds on their outer faces are flush with the periphery ofthe drill-head A. It' preferred, the toggle-arms K of the cutting-bars J may be so adjusted that they will bring up against some obstruction, and thus hold theA piston lfrom coming too near the stationary head G; or a stop may be put at any desired part of the apparatus to effect this end. The portion of the section C which is -below the stationary head G is nicely turned out and ts the piston H, which works in it. The coupling B has slots or water-ways cut out from its inner periphery at the end oi' the piston-stroke, (seen at 16,) thus practically enlarging the internal diameter of the piston-cylinder, so that there will be a passage-way for water around the piston when it is at or near the end of its stroke. The drill-rod, which, as before stated, is screwed to the piston-rod by the threads on the portion D thereof, is provided with a continuous water-way through it, connected with the forcepump, through which the water is forced.

Having thus described my apparatus, I will now describe its method of operation.

Assuming that the hole to be acted upon is avertical or practically lvertical one, my improved drill is fastened to the end ot' the'drillrod by the threads on D, and is then passed into the hole till the drill lies at the upper part of the portion to be enlarged. During thisinserton of the drill no water should be forcedthrough the rod, and the weight of the head A, the coupling B, and section C causes the several parts of the apparatus to assume the position shown in Fig. 2, thus retracting the arms and allowing the apparatus to be easily introduced into the hole. When, as before stated, the drill has reached the part of the hole to be enlarged, the drill-rod is caused to revolve, which, acting through the square portion D ofthe piston-rod and the piece F, which is keyed by the keys N to the section C, causes the drill to revolve also, and at the same time the water is forced through the water-way in the drill-rod, as usual, and it passes in the water-way 14 through D and D', and then,enteringthe upper end of E, it passes through it and out at the smaller passages, 15,

IOS

and into the space between the piston-head G and the piston H. Here itcan go not'ar'ther until,

by the continued action of the pump or head of water, as the case maybe, sufficient force is obtained to drive the cylinder-head G upward, which takes the drill with it, and as this takes place the piston-rod E,acting through the toggle-armsK,forces thecutting-barsJ outwardly, as seen in Fig. 1, and the diamonds or other cutters on them, coming in contact with the substance to be removed, cut it away. The water presses'the piston-head vG upward until the water-ways (seen at 16) come opposite the piston, and when this takes place the water can escape around the piston through these waterways 5 and further movement of the piston through the drill is stopped by the end ofthe piston E (seen at 11) reaching the bottom ot' its recess, or by some other suitable stop applied to any suitable portion ot' the apparatus. The water now passes through the lower part of the coupling B and through the spaces in which the toggle arms work, and thence through the recesses in which the cutting-arms are, and out between them and the sides of the recesses andaround their lower ends through IIO IIS

the water-passages 13 to -the outside of the drill, where the cutting is beingdone, and thus cools the diamonds and cutting-bars and carries away the detritus. After the hole has beensufticiently enlarged the forcing of the water through the rod is stopped, the weight of the parts again causes them to assume the relative position shown in Fig. 2, and the drill can then'be withdrawn from the hole. If the hole be a horizontal one or inclined upwardly from the machine, then the impingement of .the cutting-arms J against the sides of the hole will force them into their recesses, so that the drill can be easilyintroduced into the-hole.

If desired, the hole through the piston-head G may be squared, and that portion of the piston which works through it also squared. This will secure the revolution of the drill when the piston-rod is revolved, and will dispense with the square part D of the piston-rod and the piece F,`through which is the square hole for D; but thedifculty of packing a square pistonrod makes this undesirable. Also,if preferred,

' thel revolution of the drill.

thelowerextended end of the piston (shown at f 11) may be squared, as before stated, and it,

fitting into its square recess, will also effect p This may be the best method for small drills, and avoids the necessity for the squared .portion D.

lf the expansion-drill be other than a diamond drill, so that the presence of water is not necessary at the place of the cutting, then there will be no necessity for the water-ways 16, nor for any water below the piston; but even in such drills I prefer to have the water pass, so as to keep the drill clean and to moisten and `soften the earth or soft rock, and also,l to carry away the detritus.

My drills may be used with compressed air or steam as well as water, and my invention is applicable also to thread-cuttin g devices, the cutters being placed on the cutting-arms.

I claim as newi V Y 1. The combination, in an expansion-drill, of a drill-rod, a piston-rod part of which is not cylindrical, and which part works through a corresponding and rigid part of the drill, the piston-rod also working through a cylindrical head within the drill, a piston attached to the piston-rod,which piston works through a partfof the drill as its cylinder, thesaid drillrod and piston having a water-passage through them down `to the upper side of .the piston,

which there discharges between the piston and the cylinder-head, toggle-arms pivoted to the piston-rod at one end and to the cuttingbars at the other end, the cutting-bars themselves pivoted at one end to the toggle-arms and at the other end to the drill, and recesses in the drill for the reception of the cutting-bars, all combined substantially as and for the purposes set forth.

2. The combination, in an expansion-drill, of a drill-rod, a piston-rod a part of which is which there discharges between the piston and. l

the cylinder-head, a water-passage around the piston at the farther end of the stroke to allow the water to pass beyond the piston, togglearms pivoted to the piston-rod at one end and to the cutting-bars at the other end, the cutting-bars themselves `pivoted at one end to the toggle-arms and at the other end to the drill, recesses in the drill for the reception of the cutting-bars, and water-passages, so that the water can ow from below the piston to the cutting-faces of the cutting-bars, all combined substantially as and for the purposes set forth.

3. The combination, in an expansion-drill, of a hollow piston-rod, with openings from the outside to the inside of the piston-rod just abo've the piston and between it and the cylinder-head, and a piston i'astenedto it, and workin g in a suitable cylinder within the drill, the lower-end ofthe piston-rod being connected with mechanism whereby cutting-bars may be projected and retracted from the face of the drill, all combined substantially as and for the purposes set forth.

4. The combination, in an expansion-drill, of a piston-rod and piston moving` within the drill, toggle-arms attached to the piston-rod Eis at one end and to cutting-bars at the other end, and the cutting-bars themselves attached at one end to the toggle-arms and at the other to the drill. Y

5. The combination, in an expansion-drill, of a `rod and toggle-arms attached to the rod at oneend and to cutting-bars at the other end, so that when the cutting-bars are in `use the toggle-arms shall lie at substantially right an gies to the rod, substantially as and for the purposes set forth.

6.The combination, in an expansion-drill, of arhollow piston-rod, with openings from the out-side to the inside of the piston-rod between athe piston and the cylinder-head, a piston l'astened to the piston-rod andworking :in a suit- ,able cylinder within the drill, a water-passage around the piston'at the farther end of the stroke, the piston-rod being. connected with mechanism whereby cutting-bars .may be projected and retracted from the face of the drill, and water-passages from the space below the piston to the cutting-face of the cutting-arms, substantiall y as and for the purposes set forth.

SAMUEL W. DOUG'LASS. Witnesses:

J oHNv J CALDWELL, JOHN H. IvEs.

IOO

IIS

Referenced by
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Classifications
Cooperative ClassificationE21B10/322