US3237462A

US3237462A - Rock drilling rig

Info

Publication number: US3237462A
Application number: US367681A
Authority: US
Inventors: Worman Martin
Original assignee: Ingersoll Rand Co
Current assignee: Ingersoll Rand Co
Priority date: 1964-05-15
Filing date: 1964-05-15
Publication date: 1966-03-01
Anticipated expiration: 1983-03-01

Description

March 1, 1966 M, W R AN 3,237,462

ROCK DRILLING RIG Filed May 15, 1964. 5 Sheets-Sheet 1 rfii 5 2?... u 4!? FIG.

INVENTOR MART IN WORMAN BY QM mT-MJIT ATTORNEY M. WORMAN ROCK DRILLING RIG March 1, 1966 5 Sheets-Sheet 5 Filed May 15, 1964 FIG 3 INVENTOR. MART/IV WORMA/V ATTORNEY United States Patent M 3,237,462 RGCK DRELLENG RIG Martin Worman, Philiipsburg, Nah assignor to ingersoii- Rand (Ionrpany, New York, N.Y., a corporation of New .1 crsey Filed May 15, 1964, SQ!- No. 367,681 2 Claims. (Cl. 74-99) This invention relates to rock drilling rigs and particularly to mounts for supporting rock drilling apparatus.

An example of the art to which this invention relates is the US. Patent No. 2,975,993, issued to M. A. Beagan, Jr. March 21, 1961. This patent describes a prior art drill mount including a boom having an outer end portion which is rotatably mounted on the remainder of the boom and a worm and worm gear mounted on the boom for power-turning the outer end portion about the axis of the boom. This structure has the disadvantage of being prone to failure under the vibration and heavy shock loads which are normally encountered by rock drilling equipment.

The principal object of this invention is to provide a rock drill mount including a boom having an end portion which can be power-turned about the boom axis and which will reliably withstand the normal vibration and shock loads of operating rock drilling equipment.

Other important objects of this invention are: to provide an economical boom structure which can support a rock drill and power-turn the rock drill about the axis of the boom; and to provide a lock structure for preventing play in a rotatable end portion of a boom after the boom end portion has been turned to a desired position relative to the remainder of the boom and is being used to support operating rock drilling equipment.

The invention is described in relationship to the accompanying drawings wherein:

FIG. 1 is a perspective view of a track-laying vehicle carrying a boom including an embodiment of this invention;

FIG. 2 is an axial section of the end portion of the boom shown in FIG. 1, this view being broken away along line AA;

PEG. 2A is an axial section showing the remainder of the boom end section which was broken away along line AA in FIG. 2;

FIG. 3 is a section taken along line 33 of FIG. 2;

FIG. 4 is a section taken along line 44 of FIG. 2; and

FIG. 5 is an elevational View illustrating how the embodiment can be used to drill a plurality of holes located in a vertical surface and spaced along a semi-arcuate path.

The drill rig 1 shown in FIG. 1 is the crawler type and includes a chassis 2 mounted on a pair of endless tracks or treads 3 riding on suitable idler wheels 4 and driving sprockets 5. The drive sprockets 5 are driven by independent air motors 6. A boom 7 is mounted on the chassis by a connection which provides for its pivoting on the chassis in both the vertical and horizontal directions. A pair of hydraulic cylinders are provided to pivot the boom in these directions. FIG. 1 shows the cylinder 8 for moving the boom in the horizontal direction.

A conventional drill guide 119 is carried by the outer 7 3,237,462 Patented Mar. 1, 1966 This invention involves a means for rotatably supporting a rotatable member 14 on the outer end of the boom 7 for limited rotation about the axis of the boom 7 and for power-turning the rotatable member through its limited rotary movement. The drill guide 11 is carried by the power-dump connection 13 which is mounted on the end of the rotatable member 14.

The specific construction of the rotatable member 14 and its mounting on the end of the boom 7 is shown in FIGS. 2 and 2A. The boom 7 includes a hollow sleeve 1d forming the forward portion of the boom 7 and carrying an enlarged collar 17 fixed on its outer end. The rotatable member 14 is rotatably journalled in the collar 17 by a pair of axially spaced bearing rings or

bushings

18 and 19. The outer bearing ring 19 is mounted in an annular nut 2.0 having external threads and fitting in the open end of the collar 17 which is internally threaded to fit the nut 20. The rotatable member 14 includes a diametrically enlarged portion 21 which is located between the bearing sleeves 18' and 19 and has shoulders abutting the ends of the bearing sleeves to prevent the member 14 from sliding axially in the collar 17. The enlarged portion 21 of the member 14 carries a series of ratchet teeth 22 on its periphery. The purpose of the teeth 22' will be explained later.

A slide 24 is slidably mounted for reciprocation within the hollow sleeve 16. The slide 24 is cylindrical and freely rides on the interior surface of the sleeve 16. The slide 24 is fixed to the rear end of an elongated worm shaft 25 which projects forward into a hollow center 26 in the rotatable member 14. The worm shaft 25 carries a set of helically extending splines 27 fitting in corresponding internal helical grooves formed in the rear end of the rotatable member 14. Because of the provision of the helical splines 27 and corresponding grooves, the reciprocation of the slide 24 within the sleeve 14 causes the rotable member 14 to rotate within the collar 17. In effect, the rear end of the rotatable member 14 carrying the helical grooves acts like a nut fitting on the worm shaft 25.

The slide 24 is connected to the forward end of a piston rod 29 which is moved back and forth by a hydraulic cylinder (not shown) housed in the rear portion of the boom 7. This hydraulic cylinder is a conventional, double-acting cylinder and moves the piston rod 29 back and forth in the boom 7 as hydraulic fluid is fed to alternate ends of the cylinder in the usual manner.

The slide 24 is pivoted on the forward end of the piston rod 29 by means of a pin 30 which extends through both the rod 29 and the slide 24. A pair of longitudinal slots 31 are formed in the sleeve 16 and the outer ends of the pin 30 project into and ride in the slots 31 to prevent the slide 24 from turning or rotating in the sleeve 16. The pin 3t) is locked in position by a pair of snap rings 32 fitting in grooves provided in the ends of the pin outside of the sleeve 16.

It should now be apparent that the movement of the worm shaft 26 back and forth causes the rotatable member 14 to rotate about the axis of the boom 7 for a limited angle. Preferably, the splines 27 on the worm shaft 25 are arranged to rotate the rotatable member 14 through an angle of at least 180 degrees, degrees to either side of the centered position of the drill guide 10 shown in FIG. 1.

Means is also provided for locking the rotatable member 14 in whatever position it may have been turned. It is necessary to lock the member 14 rigidly on the boom 7 to prevent rotary play of the member 14 on the boom which might cause the mounting of the member 14 to rapidly deteriorate due to the normal vibration caused by the operating rock drill.

The collar 17 contains two pairs of

pivoted pawls

34 and 35 for engaging the ratchet teeth 22. The pawls 34 prevent rotation in the clockwise direction, looking at FIG. 3, and the pawls 35 prevent rotation in a counterclockwise direction.

A fluid-operating system is provided for holding the

pawls

34 and 35 in their alternate releasing and engaging positions. This is performed by alternate fluidoperated pistons forced against the

pawls

34 and 35 to move them to the desired positions. In FIG. 3, the pistons 36 are biased against the pawls to move them to a releasing position by the introduction of fluid pressure into the passage 37. The pistons 38 are forced against the pawls to move them to locking positions engaging the teeth 22. The pistons 38 are forced against the pawls by introducing fluid pressure into the passages 39. It will be understood that the application of fluid pressure to either set of

passages

37 or 39 will be accompanied with a release of pressure from the other set of

passages

37 or 39.

Operation Before moving or rotating the rotatable member 14 on the boom '7, the

locking pawls

34 and 35 are moved to a position releasing the ratchet teeth 22, as shown in FIG. 3. This is carried out by introducing fluid pressure into the passage 37 and exhausting pressure from the passage 39.

After the

pawls

34 and 35 are in their releasing position, the hydraulic cylinder operating the piston rod 29 will be operated to move the slide 24 in a direction which will cause the rotatable member 14 to turn to the desired position. If the slide 24 moves forward as shown in FIG. 2, the member 14 will rotate in a counterclockwise direction looking at FIG. 3. If the slide 24 moves rear- Wardly, the member 14 turns in a clockwise direction.

When the rotatable member 14 reaches the desired position, the slide 24 is stopped, by stopping the piston rod 29 connected to a hydraulic cylinder. Thereafter, the

pawls

34 and 35 are returned to their locking positions with the ratchet teeth 22 by exhausting pressure fluid from the passage 37 and introducing pressure fluid to the passage 39.

FIG. 5 illustrates how the rotatable member 14 can be selectively moved to a variety of positions to position the drill guide 10 for drilling an arcuately arranged series of holes 41.

Although only a single embodiment is illustrated and described in detail, it will be understood that the invention is not limited merely to this embodiment but contemplates other embodiments and variations which utilize the concepts and teachings of this invention.

Having described my invention, I claim:

1. A rock drilling rig comprising:

(a) an elongated boom;

(b) a boom end portion rotatably mounted on the outer end of said boom for rotation about the aXis of said boom and adapted to support rock drilling equipment;

(c) an elongated power-turning member slidably mounted within said boom and carrying on its surface a group of helically extending splines;

(d) an annular nut fixed to said boom end portion and having helical grooves slidably engaging said helically extending splines whereby said nut and boom end portion is caused to rotate about said boom in response to the axial sliding of said power-turning member in said nut;

(e) means non-rotatably connecting said power-turning member to said boom for preventing it from rotating relative to the boom during its sliding movement;

(f) power means within said boom for selectively sliding said power-turning member back and forth through its slide path in said boom and stopping it at any selective position in said slide path;

(g) lock means for selectively locking said boom end portion on said boom to prevent all rotary play in either rotary direction between said boom end portion and said boom;

(h) said lock means including a series of teeth on said boom end portion and a plurality of pawls mounted on said boom and adapted to engage said teeth to prevent rotary play in either rotary direction between said boom end portion and said boom; and

(i) lock operating means operable to move said lock means to an inoperative position to unlock said boom end portion for rotation in both rotary directions relative to said boom.

2. The rock drilling rig of claim 1 wherein:

(a) said lock operating means includes a pressure fluid system operable for simultaneously releasing all of said pawls from said teeth.

References Cited by the Examiner UNITED STATES PATENTS BROUGHTON G. DURHAM, Primary Examiner.

D. H. THIEL, Assistant Examiner.

Claims

1. A ROCK DRILLING RIG COMPRISING: (A) AN ELONGATED BOOM; (B) A BOOM END PORTION ROTATABLY MOUNTED ON THE OUTER END OF SAID BOOM FOR ROTATION ABOUT THE AXIS OF SAID BOOM AND ADAPTED TO SUPPORT ROCK DRILLING EQUIPMENT; (C) AN ELONGATED POWER-TURNING MEMBER SLIDABLY MOUNTED WITHIN SAID BOOM AND CARRYING ON ITS SURFACE A GROUP OF HELICALLY EXTENDING SPLINES; (D) AN ANNULAR NUT FIXED TO SAID BOOM END PORTION AND HAVING HELICAL GROOVES SLIDABLY ENGAGING SAID HELICALLY EXTENDING SPLINES WHEREBY SAID NUT AND BOOM END PORTION IS CAUSED TO ROTATE ABOUT SAID BOOM IN RESPONSE TO THE AXIAL SLIDING OF SAID POWER-TURNING MEMBER IN SAID NUT; (E) MEANS NON-ROTATABLY CONNECTING SAID POWER-TURNING MEMBER TO SAID BOOM FOR PREVENTING IT FROM ROTATING RELATIVE TO THE BOOM DURING ITS SLIDING MOVEMENT;