US443819A - Rock or earth drill - Google Patents

Description

. 7 Sheets-Sheet 1.

(No Model.)

M. G. BULLOCK. ROCK AND EARTH DRILL.

No. 443,819. Patented Dec. 30,1890.

nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn c.

(No Model.) 7 Sheets-Sheet 2. M. O. BULLOCK.

ROCK AND EARTH DRILL.

No. 443,819. Patented Dec. 30, 1890.

@fia au QM (No Model.) 7 Sheets-Sheet 3.

M. 0. BULLOCK. v ROCK AND EARTH DRILL.

Patented Dec. 30, 1890.

E a i 7 Sheets-Sheet 4.

(No Model.) I

M.0.BULLO0K. ROCK AND EARTH DRILL.

Patented De0.30,1890

if \i 1 m:

/ i w g WWW/Mm W q (No Model.)

7 Sheets-Sheet 5.

Patented'Deo. 30,1890,

(No Model.) 7 Sheets-Sheet 7.

M. 0. BULLOCK.

ROUK AND EARTH DRILL.

No. 443,819. Patented Dec. 30, 1890.

fJllmnllllllllllllll J3 UNITED STATES PATENT OFFICE.

MILAN C. BULLOCK, OF CHICAGO, ILLINOIS.

ROCK OR EARTH DRILL.

SPECIFICATION forming part of Letters Patent No. 443,519, dated December 30, 1890.

Application filed March 16, 1883. Serial No. 267,293. (No model.)

To all whom it may concern:

Be it known that I, MILAN C. BULLOCK, of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Rock or Earth Drills; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to a rock-drilling machine which, besides other features of improvement, accomplishes the insertion of the easing into the hole at the same time that the drill or reamer is cutting the hole.

The invention here set forth consists in various matters hereinafter described and claimed, and illustrated in one practical form in the accompanying drawings.

In the drawings, Figure 1 is a front elevation of a machine embodying my improvements. Fig. 2 is a vertical section from front to rear in the line 2 2 of Fig. 1. Fig. 3 is a side elevation of a bent water-feed tube and its connection with the upper end of a section of a tubular drill-rod which is driven by the machine. Fig. 4 is a vertical section of said water-feed tube and its connection with the tubular drill-rod. Fig. 5 is a side elevation of the swiveled frame of the machine with the driving mechanism connected therewith, a portion of the shell of the swivelhead being broken away to reveal particularly the feed mechanism contained therein, and the supports of the. horizontal shafts of the feed mechanism being shown in vertical section from front to rear. Fig.6 is a rear view of the swivel-frame and generally of the matters shown in Fig. 5, so far as visible from the rear exterior, certain concealed parts being shown by dotted lines. Fig. 7 is a horizontal section in the line 7 7 of Figs. 1, 5, and 6, but on the scale of Figs. 5 and 6. Fig. 8 is a vertical section of the roller-bearing seen in the lower part of Fig. 2 enlarged to a scale still larger than that of Figs. 5, 6, and 7. Fig. 9 1s a vertical section in the indirect line 9 9 of Fig. 7. Fig. 10 is a vertical section in the line 10 1t) of Figs. 1 and 11, the section of Fig.10 be ng taken in the same plane in which the section of the bearings is taken in Fig. 5 and on the same scale. Fig. ll is a transverse section of parts shown in Fig. 10, taken upon line 11 11 of said figure. Fig. 12 is a fragment of the hollow shaft and of the sliding key-shaft shown in side view in the upper part of Fig. 10. Fig. 13 is a central vertical section running from front to rear in the line 13 13 of Fig. 1 through the parts embracing the feedscrew, including the vertically movable splined clutch seen in Fig. 1 and the other parts below said clutch, being on the same scale as Fig. 5. The feed-screw is shown in side elevation. Fig. 14: is acentral vertical section of the lower end of the feed-screw, shown in side elevation in Fig. 13, and of a swiveled chuck attached thereto and of a fragment in section of the casing attached to the swiveled chuck. Fig. 15 is a side elevation of the machine-frame or swivel-head, together with the adjacent parts of the engineframe which supports it.

A is the swivel-plate or back plate of the swiveled frame, mounted, usually, on an engine-frame to turn on an axis coincident with that of the engine crank-shaft B, which is the only part of the engine or motor mechanism here shown. To the swiveled plate A is hinged the swivel-head A in the usual manner, a in this intance being the hinge, and a, the locking device by which the head A is fastened back against the platelA when the machine is ready for work. The head A constitutes a frame-work for the support of the mechanism which sustains, guides, and operates the drill-rod and the feed-screw. The swivelhead is here shown as a shell open at the front, the top plate of which, made heavy and bossed, is lettered A The bottom plate thereof is marked A From the ends of the top cross-plate A rise the parallel guide-pillars A A, tied together at the top by a cross-girt a and having fitted thereto a sliding crosshead A In this cross head is rotatably mounted a sleeve E, carrying a fixed pinion e below and a driving-chuck F. above the cross-head. The chuck E is of the usual or any suitable construction adapted to seize and turn the drill-rod C. I

C Figs. 3 and 4:, is a bent water-feed tube which is connected with the upper end or sec tion of the tubular drill-rod C by a packed joint C constructed in the usual manner to ends, respectively.

below the swivel-head.

allow the rod to freelyturn while the pipe 0 remains stationary.

Below the pinion e the sleeveEalso carries a roller thrust-bearing E (best shown in Fig. 8,) constructed to take'either an upward or a downward thrust and provided in its lower end with a screw-thread to take the upper end. of the tubular feed-screw D.

F isa feed-nutorinteriorly-tln'eaded sleeve (see Fig. 9) fitted to the thread of the feedscrew D and rotatably supported in the crossplate A of'the swivel-frame. The lower end. of the feed-nut is provided with a fiangef, having marginal notches f, andv also'with clutch-teeth f Below the feed-nut a clutchsleeve G embraces the feed-screw, being provided with teeth 9 g onits upper and lower This clutch is provided with a spline or feather which fits a longitudinal feather-way (Z in the feed-screw, and therefore rotates or is rotated by said screw.

The clutch-sleeve G is allowed a vertical movement, which is given it by means of a hand-lever G, Fig. 1, the fixed fulcrum of which is beneath the notched margin of the flange f on the sleeve-nut F. The hand-lever is provided with an arm G the end of which is adapted to enter a notch f in the flange f and will do so when the clutch-sleeve is depressed to or below its mid-position.

G is a set-screw device of obvious con struction, by which the hand-lever and clutchsleeve may be locked in any desired position.

Below the clutch-sleeve G the feed-screw D is embraced by anon-threaded loose sleeve or hub H,which carries a worm-wheel H, and the upper end of said worm-wheel hub is provided with clutchteeth 71., with which the clutch-teeth G on the sleeve G may be engaged. Finally, below the worm-wheel hub H the feed-screw D is embraced by a nonthreaded but splined sleeve I, which rotates in a bearing in the bottom plate A of the swivel-frame A and carries a fixed pinion I. (See Fig. 13.)

Back of and parallel with the feed-screw D is rotatably supporteda drivingshaft J, Figs. 1, 2, 5, and 6, having its upper bearing in the cross-girt a at the top of the guide-pillars A and its lower end stepped in the stirrup J, Fig. 5. The shaft J is provided with a fast beveled pinion 7J which meshes with the pinion'B on the engine-shaft B. It is also provided with a sliding pinion J which rotates with the shaft by means of a spline, Fig. 2, and which meshes with the pinion e, that drives the drill-rod chuck. The hub of said pinion J rotates in the cross-head A. Said shaft J is further provided with a loose pinion J" inposition to mesh with the pinion I J is a clutch splined on the shaft J below the pinion J 4 and adapted to engage with the hub of said pinion, as indicated in Fig. 6, to cause the latter to rotate with the shaft. Vertical movement is given to the clutch J 5 by means of abranched hand-lever J pivoted at j, as shown in Figs. 1, o, and 6. Finally, the shaft J is provided with a fixed pinion J immediately above its bearing in the upper cross-beam of the swivel-head.

K is a counter-shaft parallel with the shaft J and supported in long bearings in the upper part of .the swivel-head. It carries at the upper end a fast pinion K, which meshes with the pinion J 7 on the driving-shaft J, and at its lower end within the shell of -the swivelhead it is provided with abeveled pinion K which meshes with a beveled pinion L on a horizontal feed-shaft L. (Shown in side view in Figs. 5 and 10, in end view in Figs. 1 and 11, and in dotted lines in Fig. 6.)

The shaftL carries three loose pinions L L L of unequal diameter, as shown in Fig 5, which mesh with the three pinions M, M, and M fixed on the sh'aft'M, which is arranged below the shaft L and parallel therewith, as also shown in Fig. 5. The shaft M is provided with a worm M, which engages the worm-wheel H on the sleeve H, and said shaft will hereinafter be referred to as the worm-shaft. As a means of driving the worm-shaft from the shaft L through the medium of either one of the loose pinions'L L L, according to the'speed which it may be desired to give to the worm-shaft, said shaftL is made hollow, as shown in Fig-10, and is provided with a slot or opposite slots L in that portion embraced by the pinions L L and L as shown in Fig. 12.. Into the endof the hollow shaft L is inserted a shaft recesses Z for a part of their thickness, within which recesses the protruding key Z maystand and rer'olve without carrying the adjacent pinion with it; but each of said pinions for,

the remainder of its thickness is provided with slots or notches Z adapted to receive the key Z, so that when occupied by said key the pinion containing the key is made fast with the shaft and is rotated therewith. The inner or most remote pinion'L of the series is also provided with notches Z for engagement with the movable key Z.

In the sectional view, Fig. 10, the movable key is shown engaged with the smallest pinion L of the driving series, and said pinion is therefore locked with the driving-shaft L and is ro- V tated therewith, giving the lowest speed provided for to the worm-shaft. By drawing out the key into the next recess Z the shaftL and its key Z, together with the key-shaft L will rotate without carrying either of the pinions, and the same is true when the key occupies the recess in the outer or larger pinion L By means of this shifting key either of the driving-pinions may manifestly be engaged,

at pleasure. In order that the key-shaft L may be drawn out or pushed in while the shaft L is running, the handle L on the shaft L is swiveled thereto, and said handle is kept from rotation by means of a projection l thereon, which runs in a groove Z in the subjacent part of the frame which forms the bearing for the worm-shaft. (See Figs. 1, 5, and 10.)

Vith the foregoing description of the gearing and with the understanding that the drillrod 0 carries at its lower end arotar-y cutterhead 0 of any description suitable for either drilling or reaming, and that upon the lower reduced and screw-threaded end D of the feed-screw D a casing-tube D may be at tached, I will proceed to describe the mode of operation by which the machine does its work.

As before stated, the main horizontal shaft B is rotated by the engine, and its direction of motion for the advance of the drill-rod when the feed-screw D is left-handed, as shown, will be from right to left, as indicated by the arrow applied to said shaft in Figs. 5 and G. This gives amotion from left to right to the vertical shaft J, as indicated by the arrow applied to the hub of the beveled wheel J in Fig. 5. The shaft J, through the pinions J 3 and e, gives a motion in a contrary direction, or from right to left, to the drill-rod O, as shown by the arrow applied to the pinion e in Fig. 1 and to the drill-rod C in Fig.

2 and in other figures of the drawings.

The feed-screw D has a motion from left to right, (or in a direction opposite to that of the drill-rod.) which is imparted to it through the worm M worm-wheel H, and clutch G when the latter is lowered into engagement with the worm-wheel hub H. In this position of the clutch G the arm G2 011 the clutch-lever G is engaged with one of the notches f in the flange f on the feed-nut F, by which engagement said feed-nut is held from rotation. The thread on the feed-screw D being lefthanded or running downward from right to left, this left to right rotary motion of the feedscrew runs the latter downwardly through the stationary feed-nut, the speed of such downward feed depending upon which pinion of the series L L L is locked to the shaft L by the sliding key Z. In this downward movement of the feed-screw D the drill-rod O is carried down at the same speed through the connection of the feed-screw with the drillrod by means of the roller thrust-bearing E sleeve E, and chuck E, Fig. 2. The casing attached to the lower end of the feed-screw D will therefore descend into the hole at the same speed of descent as the drill-rod, so that the hole will be made or reamed at the same time and with the same rapidity that the easing is inserted therein. When the clutch G position by raising the clutch-lever J so as to bring the splined clutch J 5 into engagement with the pinion J 4 and thus cause the latter to rotate with the shaft J. This connection runs the left-handed feed-screw D rapidly upward through the stationary nut F and withdraws the casing and the drill-rod from 'the hole. Retaining thedriving engagement between the pinions J and I, as just described, and throwing the clutch G upward into engagement with the nutF (which at the same time releases said nut by withdrawing the arm G2 of the clutch-lever from engagement with the flange f of said nut) cause the feed-nut to 1'0- tate from right to left with the same velocity as that of the feed-screw, and as a consequence the drill and the casing willbe rotated in the hole without either upward or downward movement. This single rotary movement is often desirable for the purpose of keeping the drill-rod or casing free in the hole preparatory to its being advanced or withdrawn thereafter, as occasion may require.

By connecting the casing D with the feedscrew D through a swivel-coupling, one form of which is shown at N, Fig. 14:, the casing may obviously be thrust down or drawn out without rotation thereof.

' Manifestly the clutch G cannot be engaged with the worm-hub H at the same time that the clutch J 5 is engaged with the pinion J since the rotary motion given to the feedscrew by one of these drivers is opposite that given it by the other.

The construction above described, wherein the casing D is turned in a direction opposite that of the drill-rod, involves an important improvement, for reasons as follows: The casing and drill-rod are necessarily revolved in a direction to tighten the screwjoints connecting the short sections composing said casing and drill-rod. The casing is either forced downwardly with the drill without rotation or turned at a slow rate of speed .relatively to the drill-rod, it usually being desirable that the casing should revolve as it descends in order to keep in motion the loose material surrounding it, and this facilitates its descent. It has been found, however, that when the screw-joints connecting the sections of the casing and drill-rod are alike or are both provided with right-hand or left-hand threads the rapid rotation of the drill-rod within the casing produces such a rapid whirling of the water therein as to finally rotate and unscrew the lower sections of the casing to an extent sufficient to cause the complete detachment of the same, and this is liable to take place either when the casing is sunk without rotation or is turned at the usual speed in the same direction with the rod. The detachment of the lower casing-sections in the bored hole is a matter of serious inconvenience, and to avoid liabilityof such an occurrence I rotate the casing and drill-rod in opposite directions, as above pointed out, of course making the screw-joints of the casin g anddrill-rodright and left'handed to correspond with the direction in which the parts. 7 are driven.v The action of the rapidly-revolvby which the said parts are fed downwardly at the same speed and are at the same time capable of independent rotation.

The main features of construction above referred to may be carried out by the use of an apparatus dilfering greatly in its details from that herein illustrated. Forinstance, as far as the turning of the drill-rod and casing in opposite directions and the feeding of both the drill-rod and easing by a single feedscrew is concerned, the gearing for turning the casin g may act upon the casing otherwise than through the said feed-screw. Many of the particular details of construction herein shown in themselves embrace important improvements and are herein claimed as part of my invention as, forinstance, in the machine illustrated the casing is directly at tached to and is driven at the same speed as the feed-screw,therebyrenderingunnecessary a separate driving-gear for turning the casing, and this feature of the ma'chineis herein claimed as a separate improvement.

Another branch of myimprovement relates to the indication by the machine of the relation between the downward force exerted by the weight of the drill-rod and casing to the resistance opposed by the rock or'earth to the downward movement of said drill-rod and casing. Such indications are here illustrated as being obtained by means of the vertically-.

movable feed-nut F, two separate indicators F F and intermediate mechanism by which the vertical movements of the feed-nut are transmitted to the pointers on said indicators. For this purpose the cross-plate A of the swivel-head is provided with two downwardly-opening chambers F F one at each side'of the central passage for the feed-nut, on the lower side of said cross-plate, and with two corresponding chambers F F in similar positions in the upper part of said cross-beam and opening'upwardly. The two chambers of each pair are connected by a passage f3, Fig. 7, and to each chamber is closely fitted a plunger F which projects beyond the adjacent surface of the cross-plate. A yokeplate F is supported by the flange fon the lower end of the feed-nut and bears upwardly.

against the lower plungers F and a similar yoke-plate F rests upon the upper plungers F and is secured upon the upper end of the feed-nut by means of a nut or similar device figure on its dial.

' F 'As shown by dotted lines in Fig.9, the

lower pair of chambers F communicates with the gage or indicator F, and,as seen by dotted lines at the right in said figure, the upper pair of chambers F communicates with the indicator F The chambers and tubes connecting therewith are occupied by oil, glycerine, or other similar fluid, and as a result an upward movement of the feed nut F will advance the pointer on the indicator F, while a downward movement of said feed-nutwill similarly advance the pointer on the indicator F Inasmuch as this feed-nut on the one hand takes the upthrust of the drill-rod and feedscrew, which results mainly from the resistance of the rock to the drill, and on the other hand takes the downthrust of the weight-of the drill-rod and the casing, it is manifest that the relations of these two forces which act to give a vertical movement of the feednut outof its normal or practically-poised position may at all times be judged by inspection of the indicators. Thus when the hole is just started and but a single length or a few lengths only of drill-rod ,and easing are connected with the feed-screw the nut will be lifted above its normal or poised position, because the downwardly feeding force will nearly or practically equal the total resist-' ance encountered by the'drill, and the indicator F will register a correspondingly high On the other hand, when the hole is deep and the weight of the drillrod and easing exceeds the force required to overcome the resistance of the rock the feednut will stand below its normal or poised position, and the indicator F will register a correspondingly high figure on its dial. WVhen the drill-rod and casing are of such. length as to equal the average resistance of'ythe rock, the indicators will both jump alternately as ICU the resistance varies. The principal utilities of these indicators are, first, their revelation to the operator of the character or hardness of the rock or other material in which the drill is at work, by which. he may adj ustthe rate of feed to the hardness of the rock or to resistance of the work, and, second, the signal they give of the passage of the drillfrom one stratum to another and from rock into a cavity. The construction described, wherein a plurality of connected chambers is located in the cross-plate of the frame, has the ad vantages of allowing the pistons to be made tight, of keeping in practical working order in the continued operation of the machine, and of always giving the fullest indication with an almost imperceptible movementot' the feed-nut.

In a prior patent, No. 165,539, dated July 13, 1875, I have shown and described a rockdrilling apparatus having in its frame annular chambers containing annular pistons which are connected with a feed-nut and two pressure-gages connected with the chambers for the purpose of indicating the relation between the downward pressure exertedby the weight of the drill-rod and the resistance to the advance of the drill-rod caused by the rock and earth. The device for this purpose herein described is in the nature of an improvement on that set forth in the prior patent, which has been found defective in several particulars, but principally from the fact that it is exceedingly difficult to make a tight joint with an annular piston of the character illustrated in said patent. By employing a plurality of small pistons, as herein illustrated, a much more simple and economical construction is obtained and any difliculty with the packing of the pistons is entirely obviated.

' A further improvement relates toa support of the swivel-head in addition to that which it derives from the engine-frame. The swivelplate which directly connects the head with the engine-frame is at the rear part of the swiveled frame, and the weight of the drillrod and easing when long gives in the overhanging position of these parts a formidable downward strain upon the connection of the frame with the engine in lifting or lowering them. To obviate this difficulty I have shown in Fig. 1 removable legs 0 O, fitted at their upper ends to the front under surface of the swivel-frame and desirably held in place by bolts 0 0, as indicated, or in some other suitable manner. They stand in the same or practically the same plane with' the feedscrew, and therefore wholly take off the overhanging strain referred to.

The roller thrust-bearing above designated as a whole by the letter E has, as here shown, the novel feature of giving compressive strain upon the rollers in both upward and downward thrusts. It consists, essentially, of two apertured and relatively-rotatable parts, between the transverse and proximate surfaces of which are inserted friction-roliers, each of the two parts mentioned being extended both above and below the rollers. The manifest advantage of such construction is to allow of rotation with equal case whether the thrust be upward or downward. Referring to Fig. 8 as illustrating this hearingcoupling most clearly, the sleeve E (which is the upper of the two principal members of the bearing) is extended downward beyond the rollers E and is provided above them with the projecting flange E and below them with the projecting nut E each reaching outwardly about half the length of the rollers. The lower member consists of the annular part E, which rises to the upper surface of the nut E beneath the rollers, and the part E which at its upper edge extends inwardly to form an annular flange e over the outer half of the rollers opposite the flange E Between the rollers and the upper flanges E and e is inserted .a bearing-ring e, and between the rollers and the subjacent parts and E is interposed a similar ring e In this construction it is plain that the downthrust of the sleeve E-through its flange E is opposed by the part E, while the upward pull of the sleeve E or the downward pull of the casing through the member E E is taken by the nut E and the flange 6 In both cases the rollers E are subjected to compression between the bearing-rings 6' and c and said bearing-rings distribute over the whole length of the rollers the strain which they receive at their outer or inner portions only. The steel ring 6 serves merely to confine the rollers E in place. One of the two shoulders or flanges of each principal memberbeingmovablewith respect to the other, as indicated by the screwthreads by which said shoulders or parts of each member are shown connected in the drawings, the bearin g may be adjusted to any degree of closeness. Such screw -th readed connection of the parts also permits the thrust-coupling containing the rollers and bearing-rings to be joined when made of continuously-annular parts, as shown.

. IVishing it to be understood that I am not restricted to the particular devices here1n illustrated and described, and reserv ng the right to claim in a separate application for patent the novel methods and other matters herein set forth but not claimed below, I claim as my invention- 1. A rock or earth drilling apparatus comprising a drill-rod, a casing, gearing which rotates the drill-rod in one direction, and a gearing which rotates the casing in the opposite direction.

2. A rock or earth drilling apparatus comprising a drill-rod, a casing-tube, a verticallystationary feed-nut, a feed-screw threaded through the feed-nut, a thrust-bear ng rotatably connecting the feed-serewwrth the drill-rod, a gearing applied to rotate the drilltoo rod, and a gearing whichrotates the casingtube.

3. A rocker earth drilling apparatus comprising a drill-rod, a casing-tube, a verticallystationary feed-nut, a feed-screw threaded through the feed-nut,'a thrust-bear ng connecting the feed-nut with the drill rod, gearing turning the feed-screw, and gearing turning the drill-rod, said feed-screw being attached to the casing-tube so as to both turn and advance the latter, substantially as described.

4. A rock or earth drilling apparatus comprising a drill-rod, a casing-tube, a verticallystationary feed-nut, a feed-screw threaded through the feed-nut, a drill-chuck having rotatable connection with the feed-screw and engaging the drill-rod, and gearing turning the drill-chuck and feedscrew independently of each other. I r

5. In a rock-drill, the combination, with guides and a cross-head fitted to move thereon, of a sleeve mounted rotatably in the cross head, a drill-chuck attached to the upper end of the sleeve, a tubular thrust-bearing or coupling having relatively-rotatable parts attached to the lower end of the sleeve, a tubular feed-screw attached to the lower part of IIO the thrust-bearing and having the drill tended through it, a feed-nut supported by the frame, and a rotating d rivin g-shaf t geared with the sleeve to which is attached the drillchuck and th rust-beari n g.

(3. The combination, with a drill-rod, a feedscrew, and a feed-nut supported in a frame and embracing the feed -screw, of a gearing for rotating the feed-screw at a slow speed for the working operation of the drill, a second gearing for rotating the feed-screw at a relatively high velocity for rapidly raising and loweringthe feed-screw, and means for connecting and disconnecting either set of gearing with and from the feed-screw at will.

'7. The combination, with the frame of a rock-drill, of a feed-nutsupported in the frame, a tubular f ee'd-screw threaded through the feed-nut, a drill-chuck rotatablyconnected with the feed-screw, gearing which rotates the drill-chuck in one direction, gearing for rotating the feed-screw in both directions, and means for throwing said gearing into and out of engagement with the feedscrew.

S. The combination, with the frame of a rock-drill, of a feed-nut supported by the frame, a tubular feed-screw passing through the feed-nut, a gear-sleeve I-I, rotatably embracing the feed-screw, a clutch splined to the feed-screw and movable into and out of e11- gagement with the gear-sleeve, a gear-sleeve I, splined on the feed-screw, a drill-rod passing through the feed-screw, connected therewith by a thrust-bearing having relatively-rotatable parts, mechanism for rotating the drillrod, gearing for driving the sleeve H and the sleeve I successively in opposite directions, and means for shifting the gear-connections.

9. The combination, with the frame of a rock-drill, of a. feed-nut supported by the frame, a tubular feed-screw passing through the feed-nut, a gear-sleeve I1, rotatably embracing t-he feed-screw,a clutch G, splined to the feed-screw and movable into and out of engagement with the gear-sleeve, a gear-sleeve I, splined on the feed-screw, a drill-rod passing through the feed-screw and connected therewith by a thrust-bearing having relativelyrotatable parts, a casing-tube connected with the feed-screw, mechanism for rotating the drill-rod, gearing for driving the sleeve H and the'sleeve I successively in opposite directions, and means for shifting the gearconnections. v

10. The combination, with the frame of a rock-drill, of a rotatable feed-nut supported by the frame, a tubular feed-screw passing through the feed lfut, a drillrod passing through the feed-screw and connected therewith by a thrust-bearing having relativelyrotatable parts, by one of which it connects with the drill-chuck and by the other of which it connects with the feed screw, a gear-sleeve II, embracing the feed screw, a clutch G, splined to the feed-screw and movable into and out of engagement with the gear-sleeve II, a lock by which the feed-nut may be held from rotation when the clutch is engaged with the worm-sleeve, a splined gear-sleeve I on the feed-screw, driving-gear for rotating the drill-rod, variable-speed gearing for driving the gear-sleeve H, and disengageable gearing for driving the gear-sleeve I.

11. The combination, with the frame of a rock-drill, of a rotatable feed-nut supported by the frame, a tubular feed-screw passing through the feed-nut and adapted to be connected with a casing-tube, a drill-rod passing through the feed-screw and connected therewith by a thrust-bearing having relatively rotatable parts, by one of which it connects with the drill-chuck and by the other of which it connects with the feed-screw, a gear-sleeveembracing the feed-screw, a clutch splined to the feed-screw and movable into and out of engagement with the gear-sleeve H, a lock by H, and disengageable gear for driving the.

gear-sleeve I.

12. The combination, with the frame, of a feed-screw, a rotatable feed-nut, a worm-gear H, rotatable on the feed-screw, a clutch G, adapted to engage both the feed-nut, and the worm-sleeve, a lever for moving the clutch G, carrying a locking device for engagement with the feed-nut when the clutch is at or below its mid-position, a splined gear-sleeve I, gearing for driving the sleeve H, gearing for'driving the sleeve I, and means for shifting the gearing connections.

13. The. combination, with the feedscrew and the verticallymovable feed-nut, of a cross-plate of the frame provided with a plurality of connected upwardly-opening chambers and a plurality of connected downwardlyopening chambers containing a liquid, a plurality of separate circular pistons movably fitted to the several chambers and connected with the feed-nut, and two pressure-gages connected one with the upwardly-opening and the other with the downwardly-openin g chambers.

14. The combination, with the feed-screw and with the frame provided with aplurality of upper chambers F and a plurality of lower chambers F of a vertically-movable feed-nut, a plurality of separate circular pistons F protruding from the chambers, cross-plates F F connecting the feed-nut with the pistons, and two gages connected with the several sets of chambers, the latter being occupied by a suit able liquid.

15. In a-variable-speed feed-gear for rock or earth drills, the combination, with the drill-rod, feed-screw, and a swivel-head sustaining the same, of an intermediate shaft L, mounted in the swivel-head transversely to the feed-screw and drivin g-shaft and provided with a series o'f'loose unequalpinions having interior feather-ways, an annular recess between the feather-way of each pinion and that of the next pinion,alengthwise-movable part L, provided with a key adapted to engage the feather-ways and to revolve in the annular recess,-a counter-shaft mounted in the head parallel with the feed-screw, bevelgears connecting the counter-shaft with said shaft L, a shaft M, parallel with the shaft L and provided with a reversed series of unequal fast pinions meshed with those on the shaft L, and a worm on said shaft engaged with the worm-wheel on the feed-screw, substantially as described.

16. The combination, with the main frame of a rock or earth drill, of a swivel-h ead rotatably supported thereon and a removable support or supports fitted beneath the outer part of the swivel-head to aid in sustaining the weight of the drill-rod and other suspended parts.

17. A thrust-bearing for uniting the drillrod chuck and the feed-nut or other parts to be similarly connected, comprising two members one having two outwardly and the other two inwardly projecting flanges, bearing-rings engaging the projections of both members, and rollers inserted between the bearingrings.

18. The combination, with a member E, provided with a fixed flange and a movable flange E of a member composed of adjustable parts Eand E presenting inwardly-directed flanges or surfaces, rollers 13*, and bearingrings 6 and 6 above and below the rollers, said rollers and the bearing-rings being confined between the upper and lower flanges of both members, substantially as described.

Intestimouy that I claim the foregoing as my invention I affix my signature in presence of two witnesses.

MILAN O. BULLOCK.

Witnesses:

M. E. DAYTON, C. CLARENCE Poona,

Images