US2212329A - Rock drill - Google Patents

Description

is a

Aug. 20, 1940.

W. A. SMITH, JR

ROCK DRILL Filed Nov. 1, 1938 N I ls;

r u i INVENTOR W/LLMM A. 501/771, J2.

BY t e F ATTORNEY Patented Aug. 20, 1940 f UNITED srA Es {PATENT- OFFICE.

" s'olaims. (01. 1 55-45) This invention relates broadly to fluid actuated rock drills, but more particularly to a support and feeding mechanism for rock drills of the stoper type.

One object of this invention is to produce a stoper type drill with. an improved combined feeding and supporting mechanism.

Another object of this invention is to provide a stoper type drill with a self supporting mechanism engageable with the work irrespective of the position of the drill thereon.

Another object of this invention is to produce an improved stoper type rock drill forming a compact assembly, which is strong, durable and eilicient. Z

Other objects and advantages more or less ancillary to the foregoing reside in the specific construction and aggroupment of the elements peculiar to this structure, as will become apparent from a more complete examinationoi this specification.

In the drawing which illustrates the invention:

Fig. l is a side elevational view of a rock drill embodying the invention and shown in operation.

Fig. 2 is an enlarged 7 side elevational view shown partly in section of the rock drill shown in Fig. 1. 1

Figs. 3, 4 and 5 are enlarged cross sectional views of the throttle valve, each-in the same position, but taken in different planes.

Referring to the drawing, It represents a fluid actuated rock drill or drilling motor having a piston (not shown) reciprocable therein for delivering impacts to a drill steel I l slidable within a front housing 12. To the rear of the drilling motor ID, a valve housing l3 has rotatable therein by a handle 14, a throttle valve [5 provided with a centralbore l6 into which motive fluid is admitted from any suitable source of supply.

' Depending from the throttle valve housing l3 coaxially with the drilling motor Hi, there is a cylinder [8 secured in position by a pair of bolts [1, one of which is shown in Fig. 2. The

lower end of the cylinder I8 is reinforced by the provision of a bore it of a diameter materially smaller than the normal inner diameter of the cylinder, through which bore is free to slide an inner cylinder I9 extending. into the'outer cylinder I8 and having its upper end portion carrying a piston 20 having one or more packing rings 2| in fluid tight engagement with the inner wall of the outer cylinder l8. A dome nut 22 closes the upper end of the inner cylinder, while the lower end thereof isprovided with a relatively side of the front housing 52.

small bore 23 throughwhich is free to slide a feed rod 24 formed with a lower pointed end 25.

The upper end of the rod 24 carries a piston 26 secured in position by a nut 21 and equipped with one or more packing rings 28 in fluid tight engagement with the inner cylinder.

Located on one side of the drilling motor Ill, there is'a combination of cylinders and pistons similar to the one above described which includes cylinder 29 preferably formed integral with .the

drilling motor iii, and extending upwardly along Slidab-ly within, the cylinder 29 is an inner cylinder 3t carrying at its lower end a piston 31 and one or more packing rings 32, which pistons. and rings arev held in position by a dome nut 33 which closes the lower end of the cylinder 30, while the up-per end thereof is formed with a relatively small bore- 3a through which is free to slide an anchor rod 35 formed with a pointed end 36. The lower end 520 of the rod also carries a piston 31 which includes v packing ring 38 held in position by a nut 39. Closing the upper end of the other cylinder 29 around the inner cylinder 3i], there is a packing ring Ml held in place by a gland nut M, and in the inner cylinder 34 there is a similar packing .ring

42 held in operative engagement with the anchor rod 35 by a nut 43.

Within one vertical plane of the throttle valve i5 shown in Fig. 3, the throttle valve is provided r30 former being in constant communication with the atmosphere-through a port 46. The cylinder lB is capable of communication with either the groove 44 or 45 through a port 41 formed within the valve-housing i3, and opening into the upper end of the cylinder Hi, from where motive fluid may be admitted into the upper end of the inner cylinder l9 through one or more ports 48 provided through the dome nut 22. Similarly the lower end of the cylinder 29 is capable of communication with the groove M or 5 through a port49, from which end motive fluid may be admitted into the lower end of the inner cylinder 30 through one or more 'ports 50 provided through the dome nut 33. The throttle valve groove a5 is in constant communication with the throttle valve inlet port It through a radial port 5!. v

Within another vertical plane of the throttle valve l5 shown in Fig. 5, the throttle valve is provided with ,a semicircular groove 52 in con-' stant communication with the atmosphere through a port 53, and capable of cornmunicaend of the other cylinder 29. The passageway 54 may also be brought into communication with the throttle valve inlet port [6 through radial port 55, while the inner cylinder 39 may communicate with the other cylinder 29 through a port 56 formed across the wall of the former near the upper end thereof.

Within still another vertical plane of the throttle valve l5 shown in Fig. 4, the throttle valve is formed with a relatively large radial port 51 capable of communicating with port 58 for admitting motive fluid into the drilling motor 10.

In the operation of the device, let it be assumed that the throttle valve 15 has motive fluid admitted into its inlet port I6, and that the throttle tion with the atmosphere through the port 46' as shown in Fig. 3.

Similarly the anchoring mechanism including the cylinders 29 and 30, will remain in the position shown in Fig. 2 because the port 49 is also in communication with i the atmosphere via the groove 44 and the port 46, while motive fluid is admitted into the upper end of the cylinder 29 through the throttle valve port 55 and the passageway 54, and therefrom into the cylinder 30 through the port 56, thereby causing. the motive fluid to act on the pistons 3| and 31 for holding anchoring mechanism as shown in Fig. '2. In this position of the throttle valve, it will be noticed that the port 58 leading into the drilling motor 10, is out of communication with the throttle valve port 51, thereby preventing operation of the drilling motor.

When the throttle valve is moved in the counterclockwise direction in Fig. 3, the port 41 will register with the throttle valve groove 45 which is in constant communication with the inlet port l5 through the radial port 54, thereby supplying motive fluid to the piston 29 for effecting feeding motion of the drilling motor I 9 and bring the drill steel H into contact with the work. Thereafter the throttle valve i5 is rotated further in a counterclockwise direction in Fig. 3, to bring the port 49 into communication with the throttle valve groove 45. In. this instance the interior of the cylinders 30 and 29 are vented to the atmosphere through the port 56, the passageway 54, the valve groove 52 and the exhaust port 53, thereby enabling the action of the motive fluid on the piston ill to cause upward motion of the cylinder 39 and rod 35 until the rods pointed end 36 contacts the work. Subsequently, the throttle valve i5 may again be turned in a clockwise direction to bring the throttle valve port 51 with' the port 58 for admitting motive fluid into the drilling motor l9 and cause the piston reciprocable therein to deliver impacts on the drill steel II.

As the drilling operation proceeds the drilling motor i9 is gradually fed upwardly to maintain the drill steel to the work. Due to the telescopic arrangement of the cylinder l9 and feed rod 24, it will be understood that when the cylinder l9 has reached the end of its possible stroke, motive fluid admitted from the cylinder l8 into the cylinder l9 through the ports 48, will act on the piston 26 for continuing the feeding operation until the piston 25 reaches the end of the possible stroke.

Due to the engagement of the anchor rod 35 with the work, it will be understood that the drilling apparatus above described can operate automatically without the assistance of an operator holding the machine in position or against rotation. The anchor rod 36 being ofi'set relative to the drill steel II will not only support a machine, but also prevent it from rotating on its own axis. Due to the telescopic arrangement of the cylinder 39 and anchor rod 35 relative to the cylinder 29, the possible movement of the rod 36 is such that it will operate successfully under normal conditions of operation. In practice the diameters of the cylinders 29 and 39 are made materially smaller than that of the cylinders l8 and 19 respectively, thereby enabling the action of the motive fluid within the feeding mechanism to feed the drill to the work irrespective of the action of the motive fluid within the anchoring mechanism.

When it is desired to cease operation of the drilling mechanism, the throttle valve 1 l5 may again be rotated into the position shown in Figs. 3 to 5. In thisv instance the throttle valve port 51 is first moved out of communication with the port 58, thereby preventing impacts to be delivered to the drill steel I I, even though the mechanism is still held in the position shown in Fig. 1. Thereafter the port 49 will be brought into communication with the atmosphere via the throttle valve groove 44 and the exhaust port 45, subsequently the throttle valve may be rotated into the position shown on the drawing, causing the passageway 54 to be brought into communication with the throttle valve port 55 for admitting motive fluid into the cylinder 29 and therefrom into the cylinder 38 through the port 55 for causing the retraction or collapse of the anchoring mechanism as shown in Fig. 2. Simultaneously the port 41 will communicate with the atmosphere via the throttle valve groove 44 of the port 45, thereby tended to be restrictive or confining and it is to be further understood that various rearrangements of parts and modifications of structural detail may be resorted to without departing from the scope or spirit of the invention as herein claimed.

I claim:

1. A rock drilling apparatus including a drilling motor having a drill steel carried thereby, a duality of cylinders rigidly secured to the motor one being larger than the other, a fluid actuated feeding mechanism within the larger of said cylinders operable for feeding the motor into drill steel engagement withthe work, and a fluid actuated extensible mechanism within the smaller of said cylinders capable of operative anchoring engagement with the work, the size of said cyle inders calculated to enable adequate feeding of the motor to the work irrespective of the operative anchoring engagement of said extensible mechanism with the work.

2. In a drilling apparatus, a fluid actuated drilling motor, a duality of cylinders rigidly secured to said motor one located coaxially therewith and the other extending alongside of. the motor, and a set of fluid actuated telescoping'elements within each cylinder, each set being extensible in opposite direction withits innermost element engageable with the work for support ing said motor in a drilling position.

3. In a drilling apparatus, a fluid actuated drilling motor, lower and upper cylinders rigidly secured to said motor the former coaxially with the motor and the latter along its side and of an

Images