US2673452A - Apparatus for installing roof suspension bolts in mines - Google Patents

Description

APPARATUS FOR INSTALLING ROOF SUSPENSION BOLTS IN MINES Filed April 12, 1950 P. E. GLAZE March 30, 1954 2 Sheets-Sheet 1 W ffl A K (IAN INVENTOR. P404 5. 44 #215 vCQ/Jf/ ITTOKAZXS P. E. GLAZE March 30, 1954 APPARATUS FOR INSTALLING ROOF SUSPENSION BOLTS IN MINES Filed April 12, 1950 '2 Sheets-Sheet 2 "iii/II;

' INVENTOR. P404 5.641425 Patented Mar. 30, 1954 APPARATUS FOR INSTALLING ROOF SUS- PENSION BOLTS IN MINES Paul E. Glaze, Gorgas, Ala., assignor of one-fourth to Milton H. Fies, one-fourth to Harry M. J ohnstone, both of Birmingham, Ala., and onefourth to James W. Shealy Application April 12, 1950, Serial No. 155,545

My present invention relates to apparatus for installing roof supporting suspension bolts in plates in mine roofs, and includes means to force and expand the bolts into the roof and screw the usual nuts thereon for holding the roof plates in place, thus providing a unitary, simple and efficient machine which shall be adapted to perform completely the operation of installing the roof supporting bolts and securing the plates thereto.

In the art to which my invention relates, suspension bolts as a means of supporting mine roofs in coal mines has only recently come into general use. The essential operations in this system of supporting a mine roof comprise drilling a hole through that part of the immediate overburden which is likely to fall and partially into the denser, more stable earth structure next above the immediate overburden. A. bolt of about one inch in diameter and of a suitable length, usually from 3 to 4 /2 feet long, is driven or forced into the hole. The bolts may be split on the upper end for a distance of several inches, and prior to inserting them in the hole a wedge block is placed in the split end. Also other forms of expansion bolts may be employed. When a split end bolt such as herein described is forced into the roof, the wedge spreads the upper split end causing it to enter the overburden and securely anchors the bolt in the roof. The operation is completed by passing the projecting lower end of the bolt through a hole provided in a steel plate, usually a plate about inch thick and 6 inches square, and running a nut onto the lower threaded end of the bolt, thus pressing the plate firmly against the roof. These bolts are usually placed on 3 to 6 foot centers in the mine roofand consequently a large number of the same are required even in relatively small mine workings. In carrying out this operation where the overburden to be supported is on the order of 3 feet thick, the holes usually are driven about four feet deep. It is accordingly the usual practice to start the drilling operation with a short drill bit and to exchange it for a longer one during the drilling of each hole. This change of drill bits requires the operator to remove the operating tool from beneath the partially drilled hole, withdrawthe shorter bit, insert the longer one into the hole, and then bring the operating tool back again into position to engage the bit for continuing the drilling. After the hole is finally drilled to the correct depth the expansion bolt is inserted and forcedhome. Finally, the plate isrput in 4 Claims. (Cl. 61-63) place and the nut screwed on to securely hold the plate against the roof. I-Ieretofore, so far as I am aware, such drilling operations have been accomplished generally through the use of a stoper type drill apparatus or hand held rotary drill. The bolts have been driven by means of some form of percussive tool and the nuts screwed onto the bolts. Such prior method of installing bolts has been slow and cumbersome and has required considerable labor and expense.

It is the prime object of my invention therefore to provide a highly mobile, simple and efficient apparatus for carrying out the above operations which consists essentially of a motor driven rotary drilling tool mounted for vertical reciprocation and for pivotal movement in a horizontal plane, whereby through the use of a drill bit inserted in the chuck of the tool the bolt hole may be drilled in the roof, the driving mechanism lowered to disengage the same from the chuck, and be swung laterally from beneath the drill bit, permitting the same to be removed from the hole for the purpose of inserting a longer bit, or eventually, for the purpose of inserting a suitable wrench for tightening the nut.

Another object is to provide apparatus of the character designated which shall be mounted on a vehicle constructed and arranged to be translatably supported on Wheels or the like, or,

at the will of the operator, to rest directly on the bottom of the mine, thereby making the apparatus highly mobile for moving from place to place and at the same time affording a solid foundation on which the drilling, pin driving and nut tightening apparatus rests When performing these operations.

A more specific object is to provide apparatus for installing mine roof suspension bolts embodying a substantially vertically disposed fluid pressure cylinder having a plunger therein projecting from its upper end and a vertically disposed rotary power operated drill driving mech-- anism movable vertically by the plunger and having a chuck for receiving selectively the drill bits or a wrench, the driving mechanism being mounted on the plunger to overhang the cylinder, the plunger being freely rotatable in its cylinder, whereby when it is necessary to change drill bits or to insert the wrench, the driving mechanism may be swung laterally about the cylinder from beneath the hole, facilitating the changing of bits and the like and assuring realignment of the drill bit with the hole upon swinging the drilling mechanism to its original position.

Apparatus illustrating principal features of my invention is shown in the accompanying draw: ings forming a part of this applicat on in wh ch.

Fig. 1 is a somewhat diagrammaticplan view,

Fig. 2 is a side elevational VIEW. illustrating the apparatus in the process of drilling a hole into a mine roof;

Fig. 3 is a front elevationalview showing the apparatus in operating position, certain parts being broken away for the sake of clarity v Fig. 4 is an enlarged fragmental par ly sectional view of the vertically disposed fluid pressure cylinder and drill driving mechanism taken generally along line IV-IV of Fig. l and with certain parts broken away;

Fig. 5 is an enlarged fragmentai view taken generally along line VV of Fig. 4; l I

Fig. 6 is a fragmental somewhat diagrammatic view illustrating the apparatus in the process of forcing a suspension bolt into the roof Fig. "I is a view similar to Fig. 6 illustrating the apparatus set up to screw a nut onto the lower end of the bolt;

Fig. 8 is a detail isometric view of the plunger partly broken away and in section; and,

Fig. 9 is a wholly diagrammatic wiring diagram.

Referring now to the drawings for a better understanding of my invention my improved apparatus comprises a vehicle which may embody vertically disposed side frame members in the form of plates l5 and H. As best illustrated in Fig. 2 the side plates are cut generally to trapezoidal form with the longer parallel sides disposed at an angle to the horizontal. At their upper ends the plates are provided with inturned flanges l2 and i3 which are disposed to form support flanges for parts of the apparatus later to be described.

Adjacent their lower ends the side frame memberslll and II are cross connected by a plate I4 secured thereto by any suitable means such as welding. As will later appear, when the apparatus is in operating position the plate I4 rests flat on the bottom of the mine. Secured to the side frame members It! and l l rearwardly of the plate M are transverse stub axles I6 and IT. The axles carry Wheels l8 and I9 which preferably have pneumatic tires. As shown in the drawings,'the wheels l8 and I!) are so positioned that when the plate I4 is resting on the mine bottom, the wheels are raised clear thereof. Welded along the upper, longer side of the side frame members l0 and H arerearwardly extending handles 2| and 22, preferably in the form of tubes.

Secured to the lower cross .plate M as by means of bolts 23 and nuts 24 therefor is a plate 25 which forms the lower head of a fluid pressure cylinder 2'1. The fluid pressure cylinder 21 preferably is a hydraulic cylinder, and preferably is secured to the plate l4 to extend upwardly therefrom. Within the cylinder 21 is a relatively large diameter plunger 28. The plunger 28 is vertically reciprocable in the cylinder 27 and likewise is freely rotatable therein.

The upper end of the cylinder 21 maybe internally threaded as at 29 to receive an externally threaded sleeve 3| which serves as a guide for the plunger at the upper end of the cylinder. The upper end of the cylinder is exteriorly threaded as at 32 to receive a packing nut 33. A quantity of packing, indicated by the numeral 34 is placed on top of the bearing gsleeve 3i.

4 ing is compressed about the plunger and tightly seals against the egress of fluid around the plunger.

Secured to the lower end of the plunger 28 by means of a washer 36 and a stud 31 is a cylindrical bearing block 38. The bearing block 38 fits slidably and snugly within the cylinder 21, and of course moves with the plunger. As best illustrated in Fig. 8 the bearing block 38 is provided with a number of axially extending oil passages 39 aboutits periphery which afford means for fluid to pass freely about block 38.

Telescoped around the upper end of the plunger 28 is a block 4| which may be square as viewed in plan. The block 4| is secured to the plunger 28 by means of a set screw 42 threaded thereinto and engaging the plunger. Welded or otherwise secured to diametrically opposite sides of the block 4! are depending plates 43 and 44 which extend downwardly alongside the cylinder 21. It will thus be apparent that when the plunger 28 reciprocates in thecylinder 21 the block 4| moves with the plunger and carries with it the plates 43 and secured thereto.

Welded across the adjacent side edges of the plates 43 and 44 is one half of a split clamping collar indicated by the numeral 46. The half of the collar 46 carries outwardly disposed lugs 41. The other half of the clamping collar, indicated by the numeral 48, and also carrying clamping lugs 49, is disposed to coact with the half 45 in clamping between them a motor 5|. While the motor 5! may be of any suitable form, I show the same as comprising an electric motor. Driven by the motor 5| is a chuck 53 mounted at its upper end and which is usually driven through reduction gearing, not shown. The chuck 53 preferably is of the type having a hexagonal opening therein for receivingthe end of a drill rod 54, carrying the usual cutting bit, both of which are referred to herein collectively as a bit. As will appear, also, the hexagonal end of a suitable wrench may be inserted in the chuck.

The lateral stresses clue to the weight of the drilling apparatus, as wellas the down thrust of the load imposed thereon upon upward feeding movement of the drill bit by the plunger 28, may be transmitted to the side of the cylinder 21 by means of a concave roller 56, which bearsagainst the side of the cylinder and which is suitably Journaled on a pin 57 spanning the plates 43 and 44. I may provide a piece of tubing 50, closed at the bottom by a plate 52 and secured to the handle 21 for carrying drill bits and hand tools.

Secured to the flanges I2 and I3 is a cross plate 55. Mounted on the plate 55 is an electric motor 58. The motor 58 drives a self-contained hydraulic unit including a pump which is indicated generally in the drawings by the numeral 59. Also included within the unit indicated by the numeral 59 is an oil reservoir, such selfcontained units being well known to the art, and

consequently no detail description thereof is A'conduit 64 connects the other leg of the T -fit-" ting 62 to the reservoir through a manually controlled valve 66. Connected in by-pass relationship relative to the pressure line 6| is the usual safety'by-pass valve indicated in the drawings by the numeral 61.

Welded to the lower plate 4 is a vertically dis-- posed member 68. The upper end'of the member 68 may be suitably cross-braced by a member 69 welded to the member 68 and to the handle 22. The plates 43 and 44, are connected preferably at a point just above the roller 55, by a cross plate H. Secured to the plate II and extending laterally thereof, to lie substantially horizontal is a limit arm 2. The members 68 and 12 are relatively so disposed that when the drilling apparatus is swung about the cylinder 2'! a sumcient distance, limit arm I2 engages the member 68 to form a stop when positioning the chuck 53.

Electric power for the motors and 58 may be supplied to the apparatus through a three wire cable 13 from any suitable source, not shown. The motor 5i may be under control of a switch I I4, while the motor 58 may be under control of a switch 16. For convenience the switches may be located in a common box TI positioned on one of the handles, for instance the handle 22, within easy reach of the operator.

From the foregoing the method of constructing and using my improved apparatus may now be readily explained and understood. From a consideration of Figs. 1 and 2 of the drawings it will be seen that the hydraulic cylinder 2'! and the drill driving motor 5I supported therefrom are all positioned ahead of the wheels I8 and I9, so that the plate I4 upon which the cylinder is mounted normally rests on the bottom of the mine. The weight of these parts and the position of the wheels I8 and I9 is such that when thus resting on the bottom the wheels I8 and I9 are raised. This is important in that it insures the total force and weight of the apparatus in operation will be transmitted directly to the bottom of the mine and not through the wheels I8 and I9.

By grasping and lowering the outer ends of the rearwardly and upwardly inclined handles 2I and 22, the operator may raise the plate I 4 off the ground, whereupon the drilling apparatus is supported solely by its wheels I8 and I9, ready for translatory movement along the ground. In

this position the vehicle may be quite readily moved from place to place as before described. The weight of the apparatus is so distributed that when the operator lets go the handles 2| and 22 the plate I4 again engages the bottom by the force of gravity, raising the wheels I8 and I9 out of contact therewith, thus afiording a firm foundation for the working portions of the apparatus.

In use, the operator positions the apparatus so that the center line of the chuck 53 is directly beneath the point on the roof where the hole is to be drilled. By manually opening the valve 66 fluid in the cylinder 27 flows back into the reservoir, permitting the plunger 28 to move downwardly, thus lowering the drill driving motor 5I. A bit 54 of the length desired is inserted in the chuck 53; the valve 66 is closed, and the motor 58 is energized through its switch I6. This commences to pump oil into the lower end of the cylinder 2! through the opening 63, causing the plunger 28 to rise, bringing the drill bit into engagement with the roof. The motor 5I is now energized by closing the switch 14 and the drilling of the hole is commenced. The up feed for the drill 54 is accomplished by keeping the motor 58 energized to pump fluid into the cylinder 21, excess fluid icy-passing back into the reservoir through the pressure relief valve 61. The force exerted by the plunger 28 will, of course vary with the setting of the valve 61. In positioning the tool for the commencement of the drilling operation, the limit arm 12 is brought into ongagement with the vertical member 68 by rotating the plunger 28 together with the motor 5I and the plates 43 and 44, until the limit arm I2 contacts the member 68. When it becomes necessary to change a drill bit the valve 66 is opened, and the motor 58 preferably, though not necessarily, is deenergized, permitting the plunger and driving mechanism to lower. The operator now inserts a longer drill bit into the partially drilled hole, swings the'driving mechanism around until the limit arm 12 again engages the member 68, and lowers the drill bit into the chuck 53. The plunger and driving mechanism are again raised and the hole is drilled to the extent permitted by the length of the drill bit then being used. This operation is repeated until the hole is drilled to the desired depth.

The next operation consists in placing the suspension bolt A in the hole and driving the same upwardly. As shown in Figs. 6 and 7 the bolt A comprises a lower threaded end 78 and an upper split end 19. A wedge block SI is inserted into the split end '59 prior to inserting the bolt A in the hole, and in order to prevent damaging the threaded end 78 a threaded collar 82 is screwed thereon. The machine is now moved to a position such that block M is positioned immediately under the threaded sleeve 82. Pressure is again I admitted to the lower end of the cylinder, forcing the plunger 28 and the block 4| upwardly, engaging and forcing the bolt A upwardly and spreading the ends thereof by means of the wedge block 8! as indicated in Fig. 7. A suitable wrench, preferably a socket wrench, indicated by the numeral 33, having a lower hexagonal portion 84, is now inserted in the chuck 53 and the machine is moved so that the chuck is again vertically aligned with the bolt A. The roof plate having therein a centrally disposed hole 3? is placed about the threaded lower end of the bolt and a nut 85 is started onto the end of the bolt by hand. The wrench 83 is now engaged about the screwing the nut into firm contact with the plate 85. The up feed for the motor. 5! during the nut threading operation is accomplished in the manner already explained with respect to such feed for drilling'purposes.

It will be noted that in drilling the hole, when it is desired to change bits, the operator merely lowers the motor 5| with the bit 54 by opening valve 66 and then swings the entire mechanism by rotating the same laterally from beneath the hole. Stated dififerently, when the mechanism is in its lowered position, the block 4| rests on the nut 33-at the upper end of the cylinder. and

the plunger 28 together with the drill driving.

mechanism and plates 43 and, carrying the same, may be rotated about-the axis of the cyl-.

incler out of alignment with the hole being bored. The short bit is then removed and a longer one inserted in the hole and pushed up to the depth already drilled with the shorter one. The driving mechanism is rotated back under the newly inserted bit in position to receive the lower end thereof. The limit arm I2 engaging the vertical member 68 therefor affords an alignment means for assuring the positioning of the chuck 53 back under the bit. The stop means thus aiTords an easy means for re-aligning the driving mechanism with a partially drilled hole, facilitating and simplifying the operation. Similarly, the

ability of the drilling apparatus to pivot from beneath the hole aids in removing the final long not 38 and the motor 5| energized,v

accepts 7 drill bit and in re-positioning 'thelwrench '83 under the bolt when it is desired to tighten the nut.

In practice, I have found that apparatus made in accordance with my invention is easy to handle and may be readily moved about from place to place by one operator. The concave roller 55' located on the same side of the cylinder as the driving mechanism affords adequate thrust means both for the drilling operations and for the pin driving operation in the event the bolt is engaged by the block M in off-set position on the side toward the drill. In practice I have found that there are no undue strains on the apparatus either in drilling or in inserting the bolts or in driving them home.

While I show an electric motor for operating the drill and a hydraulic cylinder for raising the same it will be understood that this is for the purpose of illustration only and that, other forms of motors such as the well known rotary hydraulic motor may be used for the drill. It is important that a rotary drill and motor be employed rather than a percussive type, on account of the fact that it does not jar and loosen the overburden and does not create a dust hazard. The hydraulic pressure feed for the drill is very important in providing a steady pressure on the drill bit which could not be accomplished with a hand held drill. The amount of pressure on the drill may be varied to accommodate different kinds of rock by varying the setting of the bypass valve 61.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited but is susceptible of various changes and modifications without departing from the spirit thereof, and I, desire therefore, that only such limitations shall be placed thereupon as are specifically set forth in the appended claims.

l/Vhat I claim is:

1. In drilling apparatus, a support adapted to rest on the mine bottom, a vertically disposed hydraulic cylinder mounted on the support and having an upwardly reciprocable plungermounted therein, 'power operated drilling apparatus mounted on the side of the plunger to overhang the cylinder and carrying a vertically directed rotary drilling tool, means to maintain a constant upward pressure on the plunger, means to rotate the plunger in the cylinder to swing the drilling apparatus horizontally about the cylinder, and a limit arm operatively connected to the plunger and engageable with a member connected to the support.

2. In apparatus for installing suspension bolts in mine roofs, a support adapted to rest on the mine bottom, a vertically disposed hydraulic cylinder mounted on the support and having an upwardly reciprocable plunger mounted therein; means to maintain a constant upward pressure on the plunger, power operated tool rotating apparatus mounted on the side of the plunger to overhang the cylinder and carrying a vertically directed rotary wrench, means to rotate the plunger in the cylinder to swing the tool rotating apparatus horizontally about the cylinder, and means on the upper end of the plunger to engage a bolt and force it into position in the roof.

3. In drilling apparatus'a support adapted to rest on the mine bottom, a hydraulic cylinder mounted on the support and projecting upwardly therefrom, a plunger in the cylinder reciprocable upwardly from the cylinder and rotatable there-' in, drilling apparatus including an upwardly directed rotary drilling tool supported from the plunger and overhanging the cylinder, means to swing the drilling apparatus horizontally about the cylinder, depending arms on the upper portion of the plunger extending outwardly of and downwardly alongside the cylinder and supporting said drilling apparatus, and a roller journaled between the arms and bearing against the cylinder to take the lateral thrust on the plunger created by the drilling apparatus.

4. In apparatus for installing suspension bolts in mine roofs, a support adapted to rest on the mine bottom, a hydraulic cylinder mounted on the support and projecting upwardly therefrom, a plunger in the cylinder reciprocable upwardly from the cylinder and rotatable therein, means to maintain a constant upward pressure on the plunger, tool rotating apparatus including an upwardly directed rotary wrench supported from the plunger and overhanging the cylinder, means to swing the tool rotating apparatus horizontally about the cylinder, depending arms on the upper portion or the plunger extending downwardly alongside and outwardly of the cylinder and carrying said tool rotating apparatus, a roller journaled between the arms and bearing against the cylinder to take the lateral thrust on the plunger created by the tool rotating apparatus,

and means on the upper end of the plunger to engage a'bolt and force it into the roof.

PAUL E. GLAZE.

References Cited in the file of thispatent UNITED STATES PATENTS

Images