US930430A

US930430A - Percussive rock-drill.

Info

Publication number: US930430A
Application number: US44644908A
Authority: US
Inventors: William Charles Stephens
Original assignee: Individual
Current assignee: Individual
Priority date: 1908-08-01
Filing date: 1908-08-01
Publication date: 1909-08-10
Anticipated expiration: 1926-08-10

Description

W. G. STEPHENS. PERGUSSIVE .ROGK DRILL. APPLICATION FILED AUG. 1. 1908.

2 8HEETBSHEET l.

, Patented Aug". 10, 1909.

W. G. STEPHENS. PEROUSSIVE BOOK DRILL. APPLICATION FILED AUGL'I. 1908.

Patented Aug. 10, 1909. 2 SHEETS-SHEET 2.

N Q m: w\ R Q N N 1 5. F 0 5 WILLIAM CHARLES STEPHENS, OF CORNWALL, ENGLAND.

rnncussrvn noon-DRILL.

Specification of Letters Patent.

Patented Aug. 10, 1909.

Application filed. August 1,1908. Serial No. 446,449.

To all whom 'it may concern:

Be it known that 1,.WILLIAM CHARLES STEPHENS, a subject of the King of Great Britain, residing at Carn Brea, Cornwall, England, have invented new and useful. Improvements in or Connected with Percussive Rock-Drills, of which the following is a specification.

My invention relates to percussive rock drills of the hammer type and to that class of such drill wherein the feed motion is automatically effected by air pressure, the chief object of my invention beingto construct a drill of this class which is considerably shorter than drills of the same class as heretofore constructed and wherein the feed cylinder has been arranged behind and in alinementwith the hammer cylinder, the advantages of a short drill being not only that the drill may be worked in more cramped and narrow places orgalleries than the longer class of drill but that a relatively lon hole 4 can be bored by means of a single drill bit and without the necessity for moving the support or fixing for the drill.

According to my invention the feed cylinder instead of being arranged behind and in alinement with the hammer cylinder is arranged parallel or side by side with the same and preferably beneath it, the-said feed cylinder being-adapted to slide upon a suit able cradle to which is also anchored orsecured the rod of the piston withinthe feed cylinder.

ofenable my invention to be fully understood I will describe it by reference to the accompanying drawing, in which Figure 1 is a longitudinal sectional elevation of a percussive rock-drill constructed 5 according to this invention and ada ted. to carry a hollow drill for the supply 0 water to the bore-hole. Fig. 2 is a sectlona-l plan,

and Fig. 3 a sectional side elevation thereof. Figs. 4 and 5 are respectlvely a front-end view and a rear endsectional View of the drill. Fig. 6 is a. section on the line 6- 6- Fig. 2, and Fig. 7 is a section on. the line 7'?, Fig. 4.. Fig. 8 is a section on the line 8-8, Fig. 2 and Figs. 9 and 10 are respectively sections on the lines 9- -9 and 10-10 Fig. 8. Fig. 11 is a similar View to Fig. 10 showing adifierent'positi0n of the parts.

Fig. 12 is a section on the line 12 12,Fig.-

1 and, Fig. 1-3 is an enlarged section on the line 13-13, Fig. 2. Fig. 14 1s a plan of the "cradledetached. Figs. 15 and 16 are views.

.at right angles of a tool for removing the drill bit from its holder.

fa is the main or hammer cylinder, b the .piston thereof, and c the valve for controlling the supply of motive fluid to the said piston from the passage 0' all of which parts are of usual construction.

d is the feed cylinder arran ed parallel with the cylinder a and prefera ly beneath it and e is the cradle uponwhich the cylinder 0! is adapted to slide in uides e, e.

f is the piston of the cod cylinder the, rod f of which is anchored or secured to a bracket f on the back of the cradle. This piston may be of any suitable type but is advantageously of the type wherein the pressure fluid acts behind the piston rings to hold them in close contact with the surface of the cylinder to preventleakage, as shown clearly in Fig. 1. The motive fluid is admitted in front of the piston f through a port f from a distributing tap or cook hereinafter described, so that the pressure acting against the said piston-and the front of the feed cylinder serves to push the said cylinder together with the hammer cylinder 7 forward.

The cradle e is not permanently fixed to the support '9 for carrying the drill but is made movable thereon so that when the hammer and feed cylinders have been moved forward to an extent which is limited by the length of the cradle, the said cradle, which is normally locked to its support may be temporarily released therefrom to allow of 7 its being pushed forward upon the said support to permit of the cylinders again being fed forward in the cradle to increase the depth of the hole being drilled. It will thus be understood that a hole may be drilled the length of which is practically twice as great as -the amount of movement provided for in the. cradle, and this without changing the drill bit, as during the time that the cradle is being pushed forward, as hereinbefore described, the drill bit will be hearing against the back of the .hole and so prevent the :cylindersfrom being pushed forward with the cradle. I

' ,Any suitable means may be provided for locking the cradle e to its support 9. In practice I 'find it advantageous to provide in conjunction with the cradle guides e, c a

tions 12?, k formedon the si e of the cradleas shown, clearly in Fig. 14, the said bolt, when tightened up, looking the cradle and support 9 together.- The bolt 7L has arranged in conjunction with it a spring 2', the normal tendencyof which is to disengage the serratedv head /L from the cradle serrations h" when the tightening nut 2" is released, in order to obviate the necessity for moving the bolt by hand, and the tightening bolt [2, and nut 2" are provided with a quick thread so that a slight turn of the said nut will be suflicient to allow of-the disengagement.

The cradle support 9 is advantageously formed with a conical base 9 which fits into a correspondingly shaped socket j on the bracket 7" by means of which the drill is carried on the usual supporting bar or stand 70, this arrangement of cone and socket allowing of the ready adjustment of the drill.

The bolster Z against which the hammer piston Z) operates and which carries the drill bit m is rotated to twist the bit by means of gearing, a series of teeth at around the bolster being engaged by a gear wheel a mounted on a telescopic shaft 0, the telescopic sections 0, 0 thereof being secured respectively to the said gear wheel a and to the bracket f upon the cradle 0 so that the shaft 0 will extend as thefeed proceeds. The two sections of the telescopic shaft are connected together in such' a manner that while capable of moving longitudinally there is no relative n iotion of rotation between them. In the drawings this is effected by a key 0 on the part 0 engaging a key-way 0 in the part 0 The portion 0' of the shaft 0 carried by the cradle is provided with a handle or lever 79 for imparting rotary motion as the drilling proceeds.

For supplyingwater to the hollow drill m I advantageously provide the following ar-.

rangement, that is to say, around the bolster Z within the head a-I form a recess 9 into which the water is delivered through a passage 'r' from the distributing tap or cock hereinafter described. In the said groove or channel 91 arrange a ring 8 grooved on its inner and outer surfaces, the said grooves being connected by holes 8 .so that water passing from the passage rfiows around the outer groove and through the holes 8 to the inner groove, holes t being provided in the bolster so that the Water can then flow into the central. hole t communicating with the bit m. The ring 8 is located between two pieces of packing u, u a packing gland u also nterlng the recess 9 tomaintain the said packings tight. around the bolster. o is a groove formed in the head a and open to'the air by holes 'v, c so'that any leakage of water past the packings u, u can escape. The chamber a in the head a in which the teeth 71, on the bolster are located is also provided with a piece of packing w and metal washer to to prevent access of any water.

For controlling the supply of pressure fluid to the main piston and feed piston and of water to the drill bit m I employ a single tap or cock w having inlets w and m for the supply of the pressure fluid and water respectively. The plug w of the cock is formed with recesses w and w, the recess of being designed to connect the inlet a," with the port m which is formed in one with the ports 0 and f for supplying the main and feed cylinders while the recess m is designed to bring the inlet .22 into communication with the passage 1' to the drill bitm. The recess 00 is so arranged relatively with the recess 93* that when the plug as is turned slightly, when starting the drill, the water supply is first effected, the water passing to the cutting edges of the bit before the drill commences to work, and thus insuring the free flow of water taking place before striking the rock tobe drilled so that out portions of rock are prevented from choking the hole in the bit. By further rotation of the plug the pressure fluid is then admitted to the cylinders a and d and the drill then commences to operate the water being full on. If it is found that the water supply is excessive I provide a screw valve or regulator w in the inlet m so that'the supply can be diminished. To prevent water leaking around the drill shank within the drill holder portion of the bolster, I provide a conical hole m in the said holder, and I form the said bit' with a correspondingly shaped shank m", which when jammed back into the hole m, makes a water tight joint. For the extraction of this form of drill bit from the holder, I 'fnploy a collar mion the drill bit, and I einploy a forked wedge m Figs. 15 and 16, which is placed between the said collar, and the nose of the drill holder the fork embracingsthe drill shank. By a simple tap with a hammer'the wedge forces the collar away from the drill holder, and so extracts the drill bit.

4 Although I have described the tap a: in combination with my improved drill, the arrangement for preventing leakage between the bit and its holder and the means for extracting the bit from the holder I make no claim to these in this specification as they form the subject of another application of even date herewith Serial No. 446,450.

I sometimes apply to the rear end of the hammer cylinder a clip a which embraces either the rod of the feed piston, or the portion 0? of the telescopic shaft 0, in the drawings it. is shown embracing the latter, the chief function of this clip being to support the weight ,of the cylinder ato prevent its sliding through the cradle 0 when changing bits while boring holes at angles below or above the horizontal, and thus obviating the necessity for the operator to hold up the weight of the machine when changing the drill bit, or pointing the drill to the various angles; 2 is a screw for gripping the jaws of the clip on the rod 0 The said clip also acts as a brake when boring down holes in soft rock, to prevent too rapid feeding under .vided with lateral serrated portions, and

a piston in the feed cylinder operatively connected with the cradle, of a support for the cradle provided with clamping devices having serrated portions for engaging the serrated portions of the cradle, substantially as described.

2. In a rock drill, the combinationwith the hammer and feed cylindersarranged side by side, a cradle havin a sliding enga ement with the feed cylinder, and provi ed with lateral clam engaging portions, and a piston in said eed cylinder, operatively connected with the cradle, of a supporting bar, a bracket provided with a, clamp for engaging the supporting bar, and a vertically disposed downwardly tapered socket, a cradle support, located beneath the cradle, and provided with a tapered base pivotally engaging said. socket, means for securing said cradle support and bracket together,

and a clampingbolt disposed transversely of the cradle, and secured to said cradle support, said bolt being provided with clamping means for adjustably engaging the lateral portions of the cradle, substantially as described.

3. In a rock drill, the combination with the hammer and feed cylinders arranged side by side, a cradle having a sliding engagement with the feed cylinders, and pro-.

vided with lateral clam engaging portions, and a piston in said eed cylinder operatively connected with the cradle, of a supporting bar, a bracket provided with a clamp for engaging the supporting bar, and a vertically disposed downwardly tapered socket, a cradle support, located beneath the cradle and provided with a tapered base pivotally engaging said socket, means for securing said cradle support and bracket together, a clamping bolt extending through said cradle support, transversely of the cradle, and having serrated clam ing means for engaging serrated portions 0 the cradle, and a spring connected with said bolt and normally tending to disengage the serrated portions of said bolt and cradle, substantially as described.

4. .In a rock drill, the combination with the drill cylinder and feed cylinder arranged side by side, the drill cylinder being provided with a rotatable drill su port, a. cradle supporting said cylinders and having a sliding engagement therewith'and a piston in said feed cylinder operatively connected with said cradle, a rotatable sleeve carried by the drill cylinder, and operatively connected with the drill sup ort for rotatin the same, a rotatable sha t secured to sai cradle connected to said sleeve for rotation therewith and having a longitudinal sliding enga ement with said sleeve, and operative mec anism for rotating said shaft, substantially as described.

5. In a rock drill, the combination with the drill cylinder and. feed cylinder ar-' ranged side by side, the drill'cylinder being provided with a rotatable drillsupport, a cradle supporting said cylinders and having a sliding engagement therewith and a piston in said feed cylinder operatively connected with said cradle, a rotatable sleeve carried b the drill cylinder, and operatively connecte with the drill su port for rotatin the same, a rotatable sha t secured to sai cradle connectedto said sleeve for rotation therewith and having a longitudinal sliding engagement with said sleeve, means for rotating said shaft and an adjustable friction clamp secured to the cylinders, and frictionally engagin the said shaft, substantially as describe WILLIAM CHARLES STEPHENS.-

Witnesses! HOWARD Fox, W. H. DANIELL.