US2586773A - Blast hole drilling apparatus - Google Patents

Description

Feb. 26, 1952 c. F. BALL BLAST HOLE DRILLING APPARATUS Filed April 4, 1947 2 SHEETS-SHEET l Feb. 26, 1952 c, F, BALL 2,586,773

BLAST HOLE DRILLING APPARATUS Filed April 4, 1947 2 SHEETS- SHEET 2 @iXwin/My.

Patented Feb. 26, 1952 charles F. Ball, Franklin, 1ra., assigner to .Joy Manufacturing '(loxnp'any, fa c'orporaton 'of Pennsylvania 'Application April 4, 1947,'serial No. 139,460

Thisinventien relates to drlllingapparatus and more particularly to anfimproved lilasthole'drill-` ingapparatus having improved adjustablesupporting means and associated counterb-ala'ncing means for the drilling tool whereby the latterY ofthe drilling tool, it is generally anext'remly laborious task to effect 'adjustment of the drilling tool since it `is necessary manually to sup-` port the tool against 'pivotal 'movement on its;

pivotal mounting when Vthe clamp `or vlother lccl ing vdevice is released and sometimes `to lift-a considerable weight in adjusting it. The present invention contemplates "an yimprovement over previous drilling apparatus -by Athe provi-g sion of improved counterbalancing means asso# ciated with the adjustable supporting 'structure fi for the drilling tool and 'embodying acounterffl-claims (01.255--51-l weight arranged in a novel manner with respect to the tool mounting `whereby tool radjustment is facilitated. By the provision of :the counterweight arranged in a novelmanner withrespect latter may be easily `adjusted various angularly related positions without the 'neceesityfof manual support of the drilling `tool during such adjustment. I I

`It "is accordingly an lobject of the'presenti'nvention to provide an improved drilling apparatus having improved adjustable 'supporting l'means and associated counterbalancin'g means 'for the '30 to the pivotal mounting of the drilling tool, the l adjusted 'through a wide range of angularly riel lated positions with respect to the work. `Yet another object 'is `tov provide an improved `universal pivotal mounting for the drillingtoo'l and embodying a ball-like member carried Aby "the drill support and a socketed member carrying the drilling tool 'and receiving thefballlike'mem ber, 'together with improved means ffor clamping the socketed :member #to fsaidballelikemem# b'erin its different positions of adjustment. IA further 'object is to provide a universal 'pivotal mounting of the ball and socket type for swivelly supporting va drilling "tool and improved counterbalancing means'asSocia-ted with the pivotal mounting whereby the weight of the drilling Vtool is substantially counterbalanced in 'all positions of adjustment thereof. These and other objects and advantages of the invention will, however, hereinafter 'more fully appear.

In the accompanying drawings there is shown for "purposes of illustration one form which Vthe invention may assume in practice.

In these drawings:

Fig. 1 'is fa side elevationalyiew of 'a drilling apparatus in which an illustrative lform of tlie invention is embodied, different adjusted 'positions of thedrilling `tool being-indicated in dotted IIIS.

Fig. 2 'is a 'crosssection'al view taken Ion .line 2-'2 'of Fig. l, showing vthe mobile base of the 'drilling apparatus in front "elevation vand'with the drill supporting boom swung'into alow'ered, lateral position. I

Fig. 3 is fan'en'larged longitudinal vertical sectional 'view taken through the extensible boom frame.

Fig. '4 isa cross-sectional view taken on line 4--4'of Fig. 3.

Fig. '5 'is'a'n enlarged 'fragmentary view of the drilling tool and vits Vassociated counterbalancing means, with parts shown in vvertical section to show structural details.

'6 is a cross-'sectional view taken substantially on line 6 6 'of Fig. 5.

Fig. 7 -is a detail sectional View taken on line 1-1-'o Fig.`5, 'showing the swivel clamp.

The invention, as illustratively disclosed herein, is 'shown embodied 'in 'a blast hole drilling apparatus of the type known as a 'mobile blast hole drill especially designed `foruse in underground mines or tunnels. Evidently, the invention may be incorporated in drilling apparatus of Various other types and used for other purposes.

The drilling apparatus shown comprises a mobile base I, herein a tractor base, comprising a frame 2 supported, propelled 'and steered` by endles's-traotor'treads 3, 3 of a conventional design. Mountedion a platform carried by the baseframe, midway between the tractor treads, is apede'stal 5,1'h'ere`in preferably having` its base bolted to the platform. This ypedestal has a frame `(i swiveled thereon to turn about la vertical axis, and *this frame .ispreferably formed 'with va clamp l operated by a lever 8 for securing the swiveled frame in its different positions of adjustment with respect to the pedestal. Pivotally mounted at 9 on a horizontal axis at the upper end of the swiveled frame 6 is an elongated, tubular, boom frame I9, herein extending outwardly in advance of the base. This boom frame is axially extensible and comprises a tubular rear boom frame part II and a tubular front boom frame part I2, the latter being telescopically arranged within the rear boom frame part, for a purpose to be later explained. The boom frame part I2, as shown in Fig. 3, is provided with a longitudinal splineway I3 engaged by a spline I4 secured, as by a screw I5, to the rear boom frame part II near its forward end, and this spline and splineway connection permits axial extension of the boom frame while precluding rotation of the front boom frame part I2 with respect to the rear boom frame part I I. Carried near the outer end of the rear boom frame part II are transverse clamping bolts I6, I6 each engaging-'a pair of cooperating clamp elements I 1, I'I guided in transverse bores in the frame part II vand movable into frictional engagement with the exterior periphery of the front boom frame part I2. Each bolt I6 passes through a bore in one clamp element and is threadedly connected to the other clamp element in the manner shown in Fig; 4, and both the clamp elements are held against rotation in their bores by means of conventional pin and slot connections I8 but are free to slide. The clamp elements of each pair are constantly urged apart, toward their outer released position,.by means of a coil spring I9 arranged therebetween and surrounding the bolt, as shown. The bolts are formed with outer polygonal head portions engaging the adjacent clamp elements and shaped for engagement by a suitable turning instrument whereby the bolts may be tightened to move the clamping elements I1 toward one another. the bolts are tightened, the clamp elements are moved into frictional engagementwith the front boom part I2, firmly to clamp the latter in axially adjusted position with respect to the rear boom part I I'. For swinging the boom frame I Il in a vertical direction about its pivot 9 with respect to the swiveled frame 6, a hydraulic piston and cylinder type jack 2| has its cylinder pivotally connected at 22 at its rear end to the lower portion of the swiveled frame 6 and its piston rod 23 pivotally connected at its upper end at 24 to the underside of the rear boom part II, as clearly shown in Fig. 2. When fluid under Ypressure is supplied to this jack, the boom frame I0 may be swung in a vertical direction about its pivot, and when fluid is released from the jack, the boom frame may be rapidly lowered, in an obvious manner. By trapping fluid in the jack at the opposite sides of the jack piston, the boom frame I0 may be firmly locked in adjusted position. Universally pivotally supported, in a novel manner, at 25 at the outer extremity of the boom frame I0 is a conventional drilling tool generally designated 26. This drilling tool may assume various forms but is herein preferably of the electric type having a drilling instrument 21 driven by an electric motor 28. The drilling instrument is herein in the form of a conventional auger drill steel carrying a drill bit 29, and having its shank received in a drill chuck 30. Projecting rearwardly from the drill motor within a tubular housing 3| is a conventional drill feeding means for feeding the drillwv steel toward theA work as it is rapidly rotated in a well known mannel.

When

The improved universal pivotal mounting 25 for the drilling tool is herein preferably of the ball and socket type andA has associated therewith, in a novel manner, counterbalancing means, generally designated 32, whereby the drilling tool may be easily and quickly adjusted, without great manual labor, through a wide range of angularly disposed drilling positions with respect to the boom frame. In this improved construction, suitably fixed to the outer extremity of the front boom frame portion I2 is an axially disposed, outwardly projecting, tapered shaft 33, and the ball member34of the ball and socket pivotal mounting has a tapered socket 35 for receiving the tapered shaft and is rigidly held on the shaft by a tightening nut 36 threaded at 31 on the outer end of the shaft. The ball member 34 is keyed at 38 to the shaft 33 to x the ball member 34 against rotation with respect to the shaft. Receiving the ball member and engaging the smooth exterior spherical surface thereof are the walls of a hemispherical socket 39 formed in a drill support 40, and the drilling tool 26 has a projection 4I suitably rigidly attached to a similar projection 42 on the drill support 40. The drill support may be held in position on the ball member 34 by means of a clamping ring 43 secured by bolts 44 to the drill support; and a pair of screws atvone side of the ring have adjusting nuts 45, threaded thereon as shown in Fig. 7 and each provided with a turning lever 46. When the nuts 45 are tightened, the clamping ring 43 is drawn toward the drill support, thereby firmly to clamp the parts against movement with respect to the ball member 34. Arranged on the drill support substantially diametrically opposite from the projection 42 is an elongated projection 48 which carries a counterweight 49. y

Assuming the parts to be disposed with the drill axis parallel to and in the same horizontal plane with the boom axis when the latter is horizontal, the counterbalancing will be so effected, by properly locating the centers of mass of the drilling tool and of the counterweight and determining the mass of the counterweight, that there will be no material rotative tendency about an axis in the same straight line with the axis of the boom or about a horizontal axis passing through the center of the ball and at right angles to the boom axis. The weight distribution will also be such that when the tool axis is in the same verticalplane with and parallel to the boom axis therewill be no material rotative tendency about a horizontal axis perpendicular to the line of the boom axis at the center of the ball. In effect, the counterbalancing is eifected by so determining and locating the drilling tool and the counterweight relative to the center point of the ball that the centers of mass of the drill and counterweight are each in a common straight line passing through the center point of the ball and that the product of the mass of the drilling tool and its moment arm (distance of its center of mass from the center of the ball) is equal to the product of the mass of the counterweight multiplied by its moment arm (distance of its center of mass from the center of the ball), both distances measured along the common straight line in which the centersof mass and the center of the ball lie.

The mode of use of the improved drilling apparatus is as follows: The apparatus may be propelled about the mine by the endless tractor treads 3, 3, and steering of the apparatus may be effected, in a wellF known manner, by varying the relative speeds of the tractor treads. When the working place is reached, the boom frame may be axially extended as desired and may be swung laterally to the desiredposition and the jack 2| may be operated to vary the inclination of the boom frame. The boom frame may be extended or retracted, as desired, simply by loosening the clamp elements I1 upon adjustment of the clamping bolts I6 and sliding the front boom frame part I2 axially with respect to the rear boom frame part l I and, upon suitable adjustment, the clamp elements may again be tightened. The swiveled drill frame 6 may be locked in position simply by swinging the lever 8 to tighten the clamp l. The drilling tool 26 may be swiveled into the desired angular position with respect to the boom frame on its universal pivotal mounting 25 simply by loosening the clamp nuts 45 and swinging the drilling tool on its pivotal mounting, and thereafter the clamping bolts may be tightened rmly to hold the tool in its position of adjustment. During this latter adjustment, the counterweight 49 serves substantially to counterbalance the weight of the drilling tool thereby to make adjustment thereof comparatively easy. The counterweight is so arranged with respect to the pivotal mounting and the drilling tool that the tool support may be swung into various angular positions wherein the longitudinal axis of the tool extends along lines perpendicular to lines vintersecting the center of the ball member of the ball and socket mounting. Thus the tool may be swung arcuately through a series of positions parallel with the longitudinal axis of the boom frame, about a transverse axis in planes in which the tool lies, or about an axis at right angles to both of said axes. The counterbalance weight serves substantially to counterbalance the Weight of the drilling tool regardless of whether the drill is in horizontal drilling position, in vertical drilling position, or in any intermediate drilling position between the horizontal and the vertical.

As a result of this invention, an improved blast hole drilling apparatus is provided having improved adjustable supporting means together with associated counterbalancing means whereby adjustment of the drilling tool may be effected easily and rapidly. By the provision of the improved supporting structure including the extensible boom frame and the universal pivotal mounting for the drilling tool, a wide range of tool adjustment is possible. The particular arrangement of the counterweight with respect to the pivotal mounting and the drilling tool enables adjustment of the drilling tool through a wide range of angularly relatedpositions with comparatively little effort on the part of the operator. The structure is relatively simple and rugged in design, well adapted to meet the demands of service in underground mines. Other advantages of the invention will be clearly apparent to those skilled in the art.

While there is in this application specifically described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modied and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a drilling apparatus, the combination comprising a support, a drilling tool, a universal ball and socket pivotal means for mounting said tool on said support whereby said tool may be pivoted about said support relative to three axes which intersect at the center point of said ball and socket pivot, a counterbalancing weight for said tool for counterbalancing the latter in all of its positions of movement about said axes, one member of saidball and socket pivotal means having oppositely projecting extensions to which said tool and said counterweight are respectively rigidly secured, whereby said tool and said counterweight always move in unison, the centers of mass of said tool and said weight disposed in a common straight line passing through said center point and so spaced from said center point that the products of the mass of each of said tool and said weight by the length of its moment arm from said point are equal.

2. A drilling apparatus as set forth in claim 1, wherein a clamping device cooperates with the socketed member of said ball and socket pivotal means and includes a clamping ring engaging the ball member at the opposite side thereof from said socketed member, and bolts are provided for tightening said ring thereby to secure the drilling tool in its different positions of adjustment with respect to said support.

3. A drilling apparatus as set forth in claim 1, wherein the centers of mass of said counterweight and said drilling tool when the latter is perpendicular to the working face are disposed at opposite sides of a transverse plane passing through said center point of said pivotal mounting means and cutting through both said counterweight and said tool.

4. A drilling apparatus as set forth in claim 1, wherein said counterweight and said drilling tool are disposed diagonally opposite each other and at opposite sides of said center point, with the center of mass of said counterweight spaced forwardly of said pivotal mounting means with respect to the center of mass of said drilling tool, when the center of mass of said tool is disposed rearwardly with respect to said center point of said ball and socket pivotal means.

CHARLES F. BALL.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 659,532 Jordan Oct. 9, 1900 715,277 Leavitt Dec. 9, 1902 753,477 Drake Mar. 1, 1904 897,231 Waugh Aug. 25, 1908 1,602,375 Gibson Oct. 5, 1926 1,674,669 Stedman June 26, 1928 1,971,922 Smith Aug. 28, 1934 2,312,660 McDougall Mar. 2, 1943 2,334,576 Osgood Nov. 16, 1943 2,396,365 Feucht Mar. 12, 1946 2,415,205 Gartin Feb. 4, 1947 2,456,056 Fellay et al Dec. 14, 1948 2,480,661 y Manning Aug. 30, 1949

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