US148924A - Improvement in rock-drilling machines - Google Patents

Description

R. BRYDUN, 1. s. oAvlosoN a T. s. wAnRlN ET UN.

Rock-Drilling Machines.-

Patented March 24 1874.

NOA/18,924.

lilllllllil muummmuul 'r nrrnn Sa'rn ROBERT BRYDON AND JAMES S. DAVIDSON, OF WHITEHAVEN, AND THOMAS A. WARRINGTON, OF LEWISHAM, GREAT BRITAIN.

IMPROVEMENT IN ROCK-DRILLING MACHINES.

Specification forming part of Letters Patent No. 148,924, dated March 24, 1874; application filed December 3l, 1873.

To all whom it may concern:

Be it known that we, ROBERT BRYDON and J Arms S. DAVIDSON, of Whitehaven, in the county of Cumberland, England, and THOMAS A. IVARRINGTON, of Lewisham7 in the county of Kent, England, have invented certain Improvements in Rock-Drillin g Machines, of which the following is a specification:

Our invention relates to certain improve ments, fully described hereafter, in that class of rock-drilling machines in which the cutting or boring tool or drill is attached to and actuated by a reciprocating piston-rod, the object of our invention being to render such machines more simple and efficient in construction and operation, and less liable to derangenient than usual.

In the accompanying drawing, Figure 1 is a longitudinal section of a rock-drilling machine with our improvements; Fig. 2, a transverse section of a portion ofthe machine on the line A B, Fig. l Fig. 3, an end elevation; Fig. 4, a detached sectional view drawn to an enlarged scale; Figs. 5 and 6, longitudinal and transverse sections of a modified form of machine; Fig. 7, a sectional plan of part of the base or tripod on which the machine is supported; Fig. S, a detached view of part of said base; and Fig. 9, a sectional elevation on the line E F, Fig. 7

The interior of the steam-cylinder, shown in Fig. l, instead of being of uniform diameter throughout, as usual, is of greater diameter at the end a', which is lowermost, when the machine is in working position, than at its upper end a, and to these two portions of the cylinder are adapted corresponding pistons b and bl, both attached to the piston-rod c, to the end c1 of which the cutting tool or drill is secured in the usual manner. Our object in thus constructing the cylinders of two diiferent diameters is to permit the tool to be drawn back quickly on the return stroke, and to compensate for the loss of piston area due to the presence of the piston-rod. d is the steam-chest, within which slides the valve e. W'e dispense entirely with the usual external valve-rods, stuffing-boxes, &c., and actuate the valve e from within the cylinder through the medium of a lever, f, having its fulcrum at f1, and formed with branches f2 and f3, as shown, which are struck alternately by the two pistons, in order to operate said lever and valve. As shown in Fig. l, the return stroke has commenced, the enlarged lower end a of the cylinder being open to the steam, and the reduced upper end a being open to the exhaust. The valve c will remain in the position shown until the arm f3 of its lever f is struck and turned by the inner face of the advancing piston b1, when the said valve will be reversed or moved sufficiently to open 'the upper end a of the'cylinder to the steam, and the lower end a to the exhaust, and so on alternately. The face b2 of the piston b1 has ratchet-teeth formed upon it, with which the point f3 of the lever f engages, and thus, owing to the curvilinear movement of said lever, causes the piston, and consequently the piston-rod and drill, to be turned in the direction of the arrow, Fig. l, during their rearward movement. We prevent the accidental rotation of the piston-rod` and drill during the forward stroke by means of a bolt, g, beveled at one edge, and forced against the longitudinally grooved or channeled por tion c ofthe piston-rod by a spiral spring, h, contained in a tube, t', which is screwed into the cylinder between the two pistons, as shown in Figs. 2. and 4. The beveled end of the spring-bolt enters one of the longitudinal grooves of the piston-rod and eftectually prevents its accidental rotation during the forward stroke without interfering with its positive rotation by the lever f during the rear ward stroke. We dispense with the usual external stuffing-box in the cylinder-head for the passage of the piston-rod, and substitute in place of the same the arrangement shown in` Figs. l and 5, which consists of packingmaterial c, introduced into an internal recess on the inner side of the cylinder-head, and retained therein by aperforated washer or ring, z', which permits free access of the steam to the packing. Two parallel screw-rods, l and l', are attached to lugs k k at the opposite ends of the exterior of the cylinder, and each passes through two brackets, m m', of a casing or jacket, o, which partially surrounds the cylinder, and which so 2 Maese guides and supports the latter as to permit it to be longitudinally adjusted thereon, for the purpose of feeding or withdrawing the drill. (See Figs. l and 3.) Each screw-rod is adapted to a Correspondingly-threaded nut, a, retained between the brackets m m of the jacket, and the said nuts hL ve Worm-teeth cut upon their exterior curved surfaces into which gear worms q and g on a transverse shaft, p, adapted to bearings on the jacket, and provided with an operating handle or handles, by turning` which both nuts n may be operated simultaneously and in either direction, as the cylinder and the tool carried by the same are to be advanced or retracted. The jacket 0 is connected to the base or main supporting frame X of the machine by a universal joint, which permits the said jacket to be adjusted to and retained at any required position or angle.

The construction of this joint is as follows: A boss, r, Figs l and 3, turns on a horizontal bar, a, carried by the stand X, and to this boss is attached a headed pivot, r1, slotted, as shown, so as to receive a Wedge, s. A loose bearing-plate, t, is interposed between the bar u and the Wedge, and when the latter is tightened up by its nut s', the jacket 0 will be prevented from turning on the pivot r1 by being tightly clamped between. the head r2 of the said pivot and the wedge, and the boss 9 will, in like manner, be prevented from turning on the bar u by the plate t, which Will be forced tightly against said bar by the Wedge.

The base or stand X (see Figs. 7, 8, and 9) has three legs, v o and x, the tivo former of which are enlarged at their upper ends to form cheek-pieces, through slots in which pass the forked ends of the leg, The cheek-pieces have projections o on their inner sides, to Which are adapted corresponding notches in the opposite ends of the tubular bar u, and the Whole of said parts is rigidly secured together by a binding-screw, g/,Yas best observed in Fig. 7.

The portion of our invention Which relates to the operation of the slide-valve from Within the cylinder, thereby dispensing with external appliances, is applicable to sin gie-piston cylinders of an uniform diameter throughout, as Well as to those having two pistons; but in such case it is necessary to employ two levers, f, as shown in the modification of Figs. 5 and 6-one to operate the valve When the piston has reached the limit of its movement in one direction, and the other when it has reached the limit of its movement in the opposite direction.

We claim as our inventionl. In a rock-drilling machine, a piston, b1, adjoining the drill-rod, a smaller piston, b, and a rod connecting the two pistons, in combination with a cylinder common to both pistons, all as set forth.

2. The combination of the lever f With a piston having ratchet-teeth b2, adapted to the pointed end of said lever, as set forth, for the purpose specified.

3. The combination of the longitiulinallygrooved or channeled piston-rod with a beveled spring-bolt, g, for the purpose described.

4. The combination, substantially as described, of the internal packing z, and perforated ring or Washer e', with the cylinder and piston-rod.

5. The combination of the cylinder and jacket o with the screws Z Z', nuts a, shaft p, and Worms q q', all arranged and operating substantially as and for the purpose described.

G. rlhe combination of the threaded Wedge s, its nut s', the headed pivot r1, boss i', and bearing-piece t, With the jacket o and crossbar u of the base, all constructed and operating substantially as and for the purpose set forth.

7. The stand or tripod X, consisting of legs o, n, and a', tubular cross-bar u, and bindingscrew y, all constructed and combined substantially in the nianner described.

RGBERT BRYDON.

J. S. DAVIDSON. THGS. A. VARRINGTON.

Witnesses to the signatures of ROBERT BRY-

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