US1824477A - Rock drilling mechanism - Google Patents

Rock drilling mechanism Download PDF

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US1824477A
US1824477A US576605A US57660522A US1824477A US 1824477 A US1824477 A US 1824477A US 576605 A US576605 A US 576605A US 57660522 A US57660522 A US 57660522A US 1824477 A US1824477 A US 1824477A
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feeding
valve
piston
feed
drilling
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US576605A
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Elmer G Gartin
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Sullivan Machinery Co
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Sullivan Machinery Co
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    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21BEARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B19/00Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables
    • E21B19/08Apparatus for feeding the rods or cables; Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods
    • E21B19/081Screw-and-nut feed mechanisms

Definitions

  • My invention relates to rock drilling mechanisms, and more particularly to feeding mechanisms forrock drills ofthe stoper type.A
  • An object of my i-nvention is to provide an '5' improved feeding mechanism.
  • Another object of my invention is to provide an im'- proved feeding kmechanism for rock drills which willpermit,readycontrol of the forward feed' and will :prevent any danger of dropping back .of the drill due to momentary reduction of 'air pressure in the feed cylinder.
  • a further object of my invention isjk-to provide an improved type of feeding mechanism operative automatically to maintain the drill in proper position ⁇ relative to the work.
  • Other objects andadvantages'of my 'invention will hereinafter more fullyapp'ear.
  • Fig. 2 is a central longitudinal section through the illustrative embodiment of my improved. feedingmechanism, y F f "Fig 3 is ay transverse-section on the line 3 3 ofFig. 2. s i
  • a drilling mechanism of the stoper type which comprises a percussive motor 1 which cooperates with a drill steel'2 and' which-is adapted to'be fedtoward the work by a feeding vmechanism .
  • a feeding vmechanism generally designated 3..
  • the housing member is arranged a flange24jupon the rifle bar 11, whichflange is keyed, or otherwise suitably held', in 'nonrotatable engagement with alternateones of a 7'series of friction discs 25, whilefthe other discs are held againstrotation ⁇ withvrespect tothe housingiby keyways kin the discs engaged by splines 26 4formed or securedin the interior ofthe housing 5;.
  • a piston-27 is slidable upon a reduced-e'iitremity 28 of the rifle bar 11 and on admission of airto itsfupper surface willv force'v the ⁇ friction discs 25'into bindingen-v gagement ywith each other ⁇ and so lock the rifleV bar againstrotation.
  • VrA suitableA valve mechanism v generally"vdesignated'SO, is 'pro-- vided for the control of the movements of the piston 27 and the supply of air to the cyl- 5 ing case, Serial No. 481,974, filed July 4, 1921,
  • valve member 31L having a recess 32 ⁇ in the large end thereof to whichfluid may be admitted fromasupply line 33. ⁇ .
  • the valve is provided with a radial port 34' through which fluid may be admitted to the drilling motor 1 and in a transverse plane nearer the small end of this valve-there are arranged certain ports and grooves for the control of the piston 27 andfeed mechanism. In this plane is a circumferential groove 35' whichl is adapted tofconnect a pasv36 leading to the feed' ycylinder'with the atmosphere by way of a port atrcertain times.
  • valve 47 isf manually controllable by a grasping lever 48, the sai-ne being normally open,but adapted 'to be closed when ready to operate, 'whil'ethe valve member; 3l is conn trolledby arotatable handle 49.
  • Hel 'then turns the handle 49, the handle 48 a moving with it, and first' supplies pressureto' act upon the friction disc controlling piston 27.
  • the valve 47 As the valve 47 is opened the feed cylinder and the drilling motor will be moved upward vuntil the dril-lrsteelf 2'is disposed adjacent or engages the work.
  • the handle 48' which controls the valve47, reducing the flowV or cutting olf the supply of pressure fluid to the feed cylinder, the ratchet. mechanism preventing rotation of the rifle bar and consequently holdin-.g the drill steel in a substantially stationary posi@- tion during the spotting or starting of' the' hole and preventing the collapse of the feed.
  • Asthe hole. deepens the valve .47 will'be manipulated to maintain the necessary pres-y sure in the feed'y cylinder.
  • a-drilling motor and feeding means therefor compris.- ing a member movable with said motor, a cooperating member stationary during feeding,
  • a Ydrilling motor and feeding means therefor comprising relatively movable cylinder and piston relatively movable cylinder and piston ele-V ments, one of which is fastened to said drilling motor, means for supplying motive fluidl to said elements to effect relative movement thereof, means movable bodily with themovable one of said elements, means carried by the stationary one of said elements and cooperating with said last mentioned means and operative to cause rotation thereofon collapse of said feeding mechanism, and means for preventing such rotation while air is admitted to said elements.
  • fluid actuated feeding means comprisingl a pair of relatively movable elements Yone of which is connected to said motor, arotatable screw threaded control rod movablev with one of said elements and engageablewith the other, a fluid operated brake for controlling rotation of said control rod, a rotatable threaded nut cooperating with said control rod, and ratchet and pawl mechanism interposed between said nut and one ofsaid elements.
  • feeding means therefor comprising fluid actuated members having relative movement during feeding, and means automatically operative upon initiation of reverse movement during normal drilling for checking said latter movement while allowing free forward feeding movement, said means comprising a rotatable element, friction means for controlling rotation of said element, and means associated with said element for preventing said reverse movement except when said friction. means is released to allow rotation of saidelement.
  • feeding ymeans therefor comprising fluid actuated members having relative movement r during feeding, and means for preventing-aV reverse movement of said members ⁇ and, excessive bouncingr of the drilling motorduring drilling, while allowing free forward feeding movement
  • said means comprising ya yrotatable threaded nut carried by one of said members and a screw threaded rod cooperating with said nut carried bythe other of saidV members, means for controlling rotation of said rod, and means associated with said nut and its'y cooperating member for preventingsaid reverse movement except vwhen said controlling means is released to allow rotation-'of said element.
  • the combination of fluid actuated feeding means therefor including relatively movable elements, means for controlling relative movement between said feeding elements comprising a rotatable member, a ratchet and pawl mechanism interposed between said member and one of said elements, said mechanism and member serving to prevent relative move; ment between said elements in one direction except with a corresponding rotation of said member, and means for controlling rotation of said member.
  • feeding means comprising fluid actuated members having relative movement iii mechanism associated vwith said feeding means automatically operative While permitting vfree forward feeding movement to prevent :substantial reverse ⁇ movement :and
  • vsaid controlling mechanism includes a ⁇ rotatable control r-od and a 'fluid actuated brake for controllingii'otation of said rod.
  • feeding means comprising fluid actuated members having relative movement" during feeding, and ⁇ fluid lactuated ycontrolling mechanism associated vWith said feeding means automatically operative When pres# sure is applied theretoto prevent substantial reverse movement While permitting free for- Ward feeding movement7 and a common control means for said feeding ⁇ mechanism and said controlmechanism operative to supply pressure fluid simultaneously to both mechanisms.v
  • feeding means comprising fluid actuated members having relative movement during feeding andiiluidY operated controllingmea'ns associated Withsaid feeding members including aratchet mechanism and a rotatable :nut for connecting said* ⁇ members, said nut having a lost niotion connection'with one of said members whereby a limited amount of freeniovementfin either direction is permitted.

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  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)

Description

Sept, 22, 1931. EG. GARTIN ROCK DRILLING MECHNISM Filed July 21 YPatented Sept. 22, 1931 -s UNITEDl ASTATES.vk
ELMER G. GARTI'N, ,or-CLAREMONT; anniv' HAMPSHIR, YAss'itin-OIR"rov suLLIvAnmA- CHINERY coMPANY, A,conronairieivforMASSACHUSETTS t ROQK @nemen-meisten f- .Y
AApplication filed .Tuly 21,
My invention relates to rock drilling mechanisms, and more particularly to feeding mechanisms forrock drills ofthe stoper type.A
- An object of my i-nvention is to provide an '5' improved feeding mechanism. Another object of my invention is to provide an im'- proved feeding kmechanism for rock drills which willpermit,readycontrol of the forward feed' and will :prevent any danger of dropping back .of the drill due to momentary reduction of 'air pressure in the feed cylinder. A further object of my invention isjk-to provide an improved type of feeding mechanism operative automatically to maintain the drill in proper position` relative to the work. Other objects andadvantages'of my 'invention will hereinafter more fullyapp'ear.
`In the accompanying drawings ,I have shown-for purposes of illustration one form Y whiehY my invention may assume in practice. In these drawings, v -f i Fig. 1 is a side elevation, somewhat 'short-y ened, 'of a drilling mechanism of the type in which my improved vfeeding mechanismis adapted to be employed. Y i
Fig. 2 isa central longitudinal section through the illustrative embodiment of my improved. feedingmechanism, y F f "Fig 3 is ay transverse-section on the line 3 3 ofFig. 2. s i
In the form of my invention which I' have Y elected to show for purposes of illustration,
the same is embodied in a drilling mechanism of the stoper typewhich comprises a percussive motor 1 which cooperates with a drill steel'2 and' which-is adapted to'be fedtoward the work by a feeding vmechanism .generally designated 3.. This feedingmechanism, as
will beobserved from an inspection of Fig. 2,
is arrangedvat the opposite side-cfanfintermediate head 4 from themotorl andcomprises -a `chamber forming member, which will laterbe more fully described,v a feed cyl.-
inder 6, a feed piston `7 disposed withinthe cylinder 6,y a piston rod 8, anlabutment engaging point 9,V and mechanism for holding the drilling mechanism .adj acent the Ywork l during the-spot tingor starting of a hole and'for preventing back slip of thefeed accidentally.A It will be observed that the cylin- 1922," 'serial'iwf576,605'.Y
derf. moves relatively tothe piston'7 p remains station'aryduring feed with the point- 9 in` engagement-,With 'anysuitable abutmenty Y. fThegpiston rod 8 is bored out as at 10 to form aV chamber within'whichga screwthread-` 'mounted in the Inut".v vhich pawls cooperate with tereftliil;formed` in a ring-18fcarriedf within and in :non-rotative relation .with respectto the piston =7.Y y I'Ihe'pawls 14 and ratchet teethlf? "arefvso `arranged that l relative movement betweenv the Vcylinder 6y andthe piston'tending` to causetli'e approach ofthe; lower end of thecylinderto vthe piston may be accomplished without g rotation4 fof ltherifle bar,cwhilereverse movement, i. e. ycolla se Vof thef-.feechis only possible when the r'i e lbar rotates, Atthijspoint it should be noted that the piston rod Sisl traversedby a'longitudn nal straight spline-.way20 withwhicha key 21l carried kon the lower cylinder head coop-J erates..It will also be observed that the nut 13 *is l.providedwitha slight longitudinal play atl 21a within the piston"head,`this play being somewhat greater 'than-fthe: maximum normal penetration of ,the steel" during drill` tively heavy spring 22 israrra'ngedina recess 23 belowI thefnut' for the purpose; offforcing f the nut` as farforwardly'ast/possible; v
Y. W'ithiii the housing member is arranged a flange24jupon the rifle bar 11, whichflange is keyed, or otherwise suitably held', in 'nonrotatable engagement with alternateones of a 7'series of friction discs 25, whilefthe other discs are held againstrotation `withvrespect tothe housingiby keyways kin the discs engaged by splines 26 4formed or securedin the interior ofthe housing 5;.' A piston-27 is slidable upon a reduced-e'iitremity 28 of the rifle bar 11 and on admission of airto itsfupper surface willv force'v the `friction discs 25'into bindingen-v gagement ywith each other` and so lock the rifleV bar againstrotation. VrA suitableA valve mechanism,v generally"vdesignated'SO, is 'pro-- vided for the control of the movements of the piston 27 and the supply of air to the cyl- 5 ing case, Serial No. 481,974, filed July 4, 1921,
and comprises a conical valve member 31L having a recess 32`in the large end thereof to whichfluid may be admitted fromasupply line 33.` .The valve is provided with a radial port 34' through which fluid may be admitted to the drilling motor 1 and in a transverse plane nearer the small end of this valve-there are arranged certain ports and grooves for the control of the piston 27 andfeed mechanism. In this plane is a circumferential groove 35' whichl is adapted tofconnect a pasv36 leading to the feed' ycylinder'with the atmosphere by way of a port atrcertain times. Inthis same plane, but vspaced circumferentially from thek groove 35'-, isa second passage 38 adaptedto supply pressure to apassage 39 which leads to the vspace above the piston 27, the passage 38- terminating in a groove 40`of-suliiicient length to allow material turning of the valve "with-out interrupting connection between fthe passages 38 and 39. ln same pla-neV there is also loca-ted a groove 4I tojwhich fluid maybe supplied by a passage 42" extending along-the side of! the valve and' communicating by ai radially' eX'-` tending pasa-ge with a central chamber 44 in the valve member', which chamber communicates through Laport 4'5Y surrounded by a-,valve seat46I and controlled' bya tapered valve 47 Withlthe 'recess 32'. It will' be4 noted thatthe Vvalve 47 isf manually controllable by a grasping lever 48, the sai-ne being normally open,but adapted 'to be closed when ready to operate, 'whil'ethe valve member; 3l is conn trolledby arotatable handle 49. l' It will be observed thatv upon initial turningV of theA valve 31 from 0H position, the existing com- Inu/1iieatirni` between the .passage V36 and thel atmospheric- -port 37 willV be interrupted pressure'pwilllbe supplied to act upon the" piston 27 by way of port '38,. groove 40,v and passage 39. Y This is the position ofthe valve shown in Fig. Qandcufurther rotation of the valve, the 'groove'41 will be brought in communication `with ythe groove 36, and depending upon the? release of'thehandle48 and theopeningof the valve 47, as a" result thereof,rairwil-rlj be 'suplied tothe feed cylinder to' eectfforward feed. i
i foregoing description'the `mode.
of operation 'of my' inVen-tionwillbe readily apparent.. Let it be assumed that thedrill is shut downz- Nov airis then supplied Vto the passages 3'6- and 39 andthe first of these passages isconnected by the groove 35 with the atmospheric port' 37. Thedrill runner* takes holid'o'f the handles 48 and 49 with one hand and moves the handle 48 to close the valve- 47.
Hel 'then turns the handle 49, the handle 48 a moving with it, and first' supplies pressureto' act upon the friction disc controlling piston 27. This locks the rifle bar against rotation relative to the feed cylinder and as further turning of the valve 31 starts the motor and opens communication under control of the valve 47 between the recess 32 and the passage 36` leading to the feedcylinder, it will be noted that the drill may be run and forward feed at any desired rate accomplished, the rate or force of feed depending upon the total period of open position of the valve 47. As the valve 47 is opened the feed cylinder and the drilling motor will be moved upward vuntil the dril-lrsteelf 2'is disposed adjacent or engages the work. The operator then manipulates the handle 48' which controls the valve47, reducing the flowV or cutting olf the supply of pressure fluid to the feed cylinder, the ratchet. mechanism preventing rotation of the rifle bar and consequently holdin-.g the drill steel in a substantially stationary posi@- tion during the spotting or starting of' the' hole and preventing the collapse of the feed. Asthe hole. deepens the valve .47 will'be manipulated to maintain the necessary pres-y sure in the feed'y cylinder. As forward feed; takes place, the'riiie bar,'whichcannot turn ony account of its being held vby the friction discs, will` cause the rotation ofthe nut v13, the: pawlssiipping overV the ratchet during this opera-tion. Thiswill result in the drill being held at all timessubstantialy upY again-st the work, but by reasonof the clearance below benut, there will be sufficient Vplay to permit' rotationofthe steel without binding.. .There nl,
will be no chance, however, of excessive bouncing of they motor back' from the end of the steel and so no: danger ofthe steel evergetting Yfar enough from the bottom of the hole to permit its being driven completelyout of thefchuch,V When itis. desired to lback out of the hole, this can be very readilyzdone. The motor willbe shutdown, the feed' cylinder will connected to the'v atmosphere by Way of the groove 35, and the chamber abovey the pistou 27 willi also be connected' with the atmosphere whereby the friction discs will be released and the nut.. as the parts telescope, may causerotation of the rifi'e' bar' freely.4 It is obvious that the reverse movement of the feed cylinder 'relati've to the feed piston 7 maybe either checkedor prevented at vwill by suitable manipulation of the valve 31 controlling duid flow through the passage 39 communicating with the bore at the vupper side of the plunger 27. f
Y VVhil'eI havefin this application specifically described oneformw-hichmy invention may assur-ne inpractic'e, Ait will be understood that this form of the same-is shown for purposes of illustration and thatv the invention maybe modified and embodiedin other forms' With out departing from its spi-rit or they scope. of
the appended claims.
What I claim as new and desire to secureby Letters Patent is:
1. In a rock drilling mechanism, a-drilling motor and feeding means therefor compris.- ing a member movable with said motor, a cooperating member stationary during feeding,
means for supplying air to effect relative movement of said members to advance said motor, and means including a cooperating ratchet and screw mechanism for preventing reverse movement thereof, thek cooperatingy parts of said. mechanism being carried respectively by said members.
2. In a drilling mechanism, a Ydrilling motor and feeding means therefor comprising relatively movable cylinder and piston relatively movable cylinder and piston ele-V ments, one of which is fastened to said drilling motor, means for supplying motive fluidl to said elements to effect relative movement thereof, means movable bodily with themovable one of said elements, means carried by the stationary one of said elements and cooperating with said last mentioned means and operative to cause rotation thereofon collapse of said feeding mechanism, and means for preventing such rotation while air is admitted to said elements. f
4. In a rock drilling mechanism having an impact motor, the combination of fluid actuated feeding means therefor comprisingl a pair of relatively movable elements Yone of which is connected to said motor, arotatable screw threaded control rod movablev with one of said elements and engageablewith the other, a fluid operated brake for controlling rotation of said control rod, a rotatable threaded nut cooperating with said control rod, and ratchet and pawl mechanism interposed between said nut and one ofsaid elements. Y
5. In a rock drilling mechanism having a drilling motor, the combination of feeding means therefor comprising fluid actuated members having relative movement during feeding, and means automatically operative upon initiation of reverse movement during normal drilling for checking said latter movement while allowing free forward feeding movement, said means comprising a rotatable element, friction means for controlling rotation of said element, and means associated with said element for preventing said reverse movement except when said friction. means is released to allow rotation of saidelement. Y 6, In a rock drilling mechanism, the combination of feeding ymeans therefor comprising fluid actuated members having relative movement r during feeding, and means for preventing-aV reverse movement of said members `and, excessive bouncingr of the drilling motorduring drilling, while allowing free forward feeding movement said means comprising ya yrotatable threaded nut carried by one of said members and a screw threaded rod cooperating with said nut carried bythe other of saidV members, means for controlling rotation of said rod, and means associated with said nut and its'y cooperating member for preventingsaid reverse movement except vwhen said controlling means is released to allow rotation-'of said element. f
7. Ina Afeeding mechanism, a plurality of Y trolling rotation of said rod, and means as- Y sociated with said rod -for preventingV said reverse movement Yexcept when said fluid actuated means is released to allow rotation `of said rod.
8.*In af-rock drilling mechanism having a drilling motor, the combination of fluid ac-v tuated feeding means therefor comprising lrelatively movable elements, and .meansy for checking said relative movement in one directionwhile permitting free movement in the opposite direction to prevent excessive bouncing of said drilling motor during drilling, said means comprising a rotatable screw threaded rod, fluid actuated friction means for controlling rotation of said rod, and means including a rotatable threaded nut associated with said rod for preventing relative movement of said elements except when said fluid. actuated friction means isreleased to permit rotation of said rod.
v9. In a rock drilling mechanism, the combination of fluid actuated feeding means therefor including relatively movable elements, means for controlling relative movement between said feeding elements comprising a rotatable member, a ratchet and pawl mechanism interposed between said member and one of said elements, said mechanism and member serving to prevent relative move; ment between said elements in one direction except with a corresponding rotation of said member, and means for controlling rotation of said member.
. l0. vIn a rock drilling mechanism, the combination of feeding means comprising fluid actuated members having relative movement iii mechanism associated vwith said feeding means automatically operative While permitting vfree forward feeding movement to prevent :substantial reverse `movement :and
bouncing. Y i Y e 11..-In aroc'k drilling inechanism,'the coinbination set `:forth in'claim 10 wherein vsaid controlling mechanism includes a `rotatable control r-od and a 'fluid actuated brake for controllingii'otation of said rod.
12. In a rock drilling mechanism,'the coiny bina'tion of feeding means .comprising fluid actuated members having relative movement" during feeding, and `fluid lactuated ycontrolling mechanism associated vWith said feeding means automatically operative When pres# sure is applied theretoto prevent substantial reverse movement While permitting free for- Ward feeding movement7 and a common control means for said feeding `mechanism and said controlmechanism operative to supply pressure fluid simultaneously to both mechanisms.v
13. In a rock drilling meclianism,'the combination of feeding means comprising fluid actuated members having relative movement during feeding andiiluidY operated controllingmea'ns associated Withsaid feeding members including aratchet mechanism and a rotatable :nut for connecting said*` members, said nut having a lost niotion connection'with one of said members whereby a limited amount of freeniovementfin either direction is permitted.
Inztestimony WhereofI alfixmy signature.
yELMER Gamin.
US576605A 1922-07-21 1922-07-21 Rock drilling mechanism Expired - Lifetime US1824477A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2801615A (en) * 1954-02-19 1957-08-06 Gen Motors Corp Actuator with multiple disc type locking means
US2804053A (en) * 1954-04-14 1957-08-27 Gen Motors Corp Actuator and locking means therefor

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2801615A (en) * 1954-02-19 1957-08-06 Gen Motors Corp Actuator with multiple disc type locking means
US2804053A (en) * 1954-04-14 1957-08-27 Gen Motors Corp Actuator and locking means therefor

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