US1063194A - Engine for rock-drills. - Google Patents

Description

G. H. GILMAN. EHGINB Fon Rumi DRILL's.

Ayrimumn mmv JAN. a, 1911.

Patented June 3, 1913.

H. my@

, Izmwenf .f

Witnesses QV/2M To'czZZ 107mm it may conf-ern:

Beit known that' I, GEORGE H. GILNAN,

a citizen of the United States, and a resident' of Claremont, county of Sullivan, Stateof New Hampshire, (whose'post-ofiice address is Claremont, New; Hampshire,) have in vented an Improvement in Engines for Rock-Drills or the Like, ot which the f'ollowing description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts. A

This'invention relates to engines andmore particularly, though not exclusively, to engines ofthe direct-acting type such as are used in connection withrockdrills and other stone working machines.

My invention will be best understood by.

reference to the following description when taken in connection with the accompanying illustration of one specific embodiment thereof, while its scope will be more partieularly .pointed out' in the appended claims.

In the drawings: Figure" 1 is a sectional elevation taken through the cylinder and Valve chamber of a rock drill embodying fone form of my invention; and Fig. 2 is a transverse sectional elevation on the line 2-2 in Fig. 1.

Referring to the drawings and more particularly to Fig'. 1, I have there shown-for the purpose of illustrating the principal teatures of the invention, the 'piston 1' a-nd y cylinder 2"ot` a rock drill. The piston rod 3, which projects through 'the forward cylinder head 4 and the feed screw 5 are shown broken away, but these' parte, as well as the cutting-tool to which the forward end of the piston rod is attached and the tool hold- 40' ing chuck, may be ol any suitable or well known construction and do not materially concern the herein-described invention.

Referring more particularly to the controlling valve 6 the latter is of the pressurevractuated piston type having a central head `for vspool '7 `which alternately connects the supplyj chamber 8."jwith. the por d O, {"thle former leading* to. thereai 40I' ltad end" `l`ofthe A`-`Cylinder immediately in ,front o t the "-5O'Sre`a'i head 'or butter 11,fandftlielatter` tofthe 4 forwarder tool end of the ,cylinder immedif atelyfbehind'tl'ie front cylinder-head 4.' The 'l engine may be used with steam, air, 4or other v pressure fluid. In the' position of the valve speiaeatin of Letters ratent. Application filed-January 3, 1911.

' groove 19 communicateswith .by means ot' longitudinal v01 valve is thrown to one pfor Vexample the posit' over,the pressureoftheisu'ij y ,the smaller end head'u'ntil the pressure li'uid end'zof the valve.

Y chloeefii H. GILMAN, or cLAREMoN'r, NEW HAMPSHIRE, AssrGNoR aso-SULLIVAN MACHINERY COMPANY, or CLAREMONT, NEW HAMPSHIRE, CORPORATION or MAINE. Y f

ENGINE FOR ROCK-DRILLS.

Patente d une 3.

vseriaiNo.600,403.

shown, the pressure tluid 4passes'from.fthe 55 supply chamber 8 thro' gh the port; 9: t'o Athe head end of the cylinder, "acting to drive the Vpiston forward, the pt )rt` 1() being. at` the same time connected about the contracted' or stemk portion of the valve, with vone end of the exhaust space 12; When the "valve is lreversed,tl ie port 10 is 'connectedvwiththe supply chamber 8 andthe head V:end lport 9 with the pposite end ofthe exhaust space" 12. To reverse the valve thelatter'sj'pro- 65 vided at opposite endswith thesp'ools.l 13 and 14 which work in end'chambers'to which pressure is alternatelyfadmitted by the in ovement of the piston to throwthe valveffThe "chamberfcontaining the head connected lby a passage 15 (see dottedlines) leading to the groove 16 in the Walls ofthe cylinder, andthe chamber containing the'jhead`-14 is connected by means of the passage 1'( (seel dotted lines) withthe` groove 18 in thecylin- 75 der walls. These groovesare alternately uncovered by the reciprocatory movement o the piston, the uncovering of a- 'groove serv-ing to 'admit pressure to that; lendfolt''the' Valve chamber with which thesaid groove 8D is connected, such admission of pressure fluid reversing the position fofY the valvenfIhe Huid pressure is exhaustedfrom' 'that end "of the valve chamber opposite thel end' td" which pressure is .admittedbymeansof a circumferential groove k19 in the wallsizof the cylinder midway the length tlf'ie'redt", 'such groove (see Fig. l)y having eonnectionfuith the external atmosphere through thefexhaust pipe oropening 20." The circumferential 90 groove or Vre- @fllt-@e Pi-Sinon .5. Y 29 so that. one end or the'fothen f 'ithe chamber is kept free fro if'ifjires'sureflui ing substantially the vfull stroke'otftt duced portion 21 in thewwall ton. The spool 7 is j otfgreater d1. ieter than the lspools 13 and 151 it is t main met o thesupply iurd 'against'ftl is admitted: as'rlesciibed. a, "ain;irt ,the eppo y This particulai" forni of valve' `and the' arrangement of controlling passagesmay be varied within wide lilflitsmf,

or other forms'of l'valves may be substituted 'withoutdeparting from the spirit of my in'- vention hereinafter more fully described.

In theoperationofarrock drill or the like it is' frequently 4Ijetp'ii'red to work the piston 11g-and down inthe cylinder without doing e ective work-and wit-hout' permitting the 'iston lto s'trihefeither the upper or the lower ed, v'thisbe1ng necessary, roi" example, *to n Y t as follows: `When the piston moves back on clear outV the hole or impartA proper-alinement to`-thedr1lL,-steel `in thecase ot a deflected-hole. .The up Vor back stroke'- may be f readilyfcontrolled on account of the Weighta'nd inertia of the 'tool o'r tools, but for the u. cushioning ofthe working] stroke. none of l*fflfhas been thoroughly satisfactory. @inthe illustrated form of tool AI- have provided a cushioning valve-24 located transversely the fool end port and adapted to prevent the escape-:of: fluid pressure from the forwardA end of the'cylinder, thereby to cushion the' forward orvdow'nward lstrokeotthe tool,

such valve, however, being so constructedl that the' pressure required'to produce the necessa y cushion is' automatically 'built up and maintained. '-Referring to' Figs..il and 2, thdvalve 24 ismountediin a chamber ransv'ersely the cylinder walls 'and is pro-I vided with the exteriorhan'dle 25 by means of which vit maybe set in the position shown in Fig. I against the stop 2.6 or turned to a position approximately 'ninety degrees therefrom a ainst the stop 27. The 'valve is intersectedy the transverse passage 2S and 'is 'also provided with 'the passage 29 at right angles thereto. Fig.v 1,- pressure-fluid passes freely throu h the transverse assage-28 to and from' tilde stroke of the piston, the valve isturned to its opposite position, bringing the passage 29 into-registration with that portion 'of the port .10'l'eading `to' the valve chamber and 'cutting olf the opposite portion ol the port and the .forwardend of the cylinder from direct co unication with. the-valve char'nloer.` this ition of the-valve lthe vpressure fluid 4ca o escape from the forward end` of passage (see Fig. 2) communicating with I the passage 29 and opening at the end thereof y. opposite the handle -25 whereat it forms a assent fora check valve 30. The latteris the many cushioning devicesA utilized therev A.the'full -area thereof, while at thebottom of In the position shown 1nforward end o the cylinder.- When, howaver, 1t' is desired to cushion the forward- 'guidedupon the reduced .end of the threaded plug 31, employed to close the .end ofthe cushioning valve chamber, and is pressed against its nseat bymeans ofthe coiled spring 32.- Nhen thevalve lifts, it admits pressure fluid from the axial passage to a groove 33 and -thencethrougli the port 34 to the cylinder in iront of the piston.

'The-operation oi the cushioning valve is ,Y vv5 its return strole, the controlling valve -G has a relation which is opposite to that shown 1n l3`ig. '1.V ylitt that time the pressure luid supply is connectedto the port l0, but the latter is .disconnected from the` forward end of the cylinder excepting through -the check valve 30. fis-the piston moves back the small amount of-.pressure-luid trapped in the'forward end of theI piston-expands.' As soon vas thepressure of the cylinder falls below the .supply pressure, however, the check. valve 3() lifts and permitspassage of pressure ,iuid from the porti() -and the supply .space to the forward end of' the'cylinder. The' pressure-Huid will., therefore, be 'admitted through vthegcheck valve. until the valve-6 reverses thepositionxand connectsthe port l0 to the exhaust. .The pressurefluid 4infront ofthe piston, however, being unable to .escape is't-rapped thereat andforms a'V- high 'pressure ycushion checking theA tor- Ward movement of thepiston. The weight of the. drill steels and the fact that the pressure-fluid at the top of the pistonacts against the piston it acts against a lesser area only, causes afjorward or downward movementof Athe piston 'to take place against the cushion.'

This movement, however, is quickly Ichecked by the cushion and the piston is returned," this 'effecting the desired reciprocatory movement of the toolf The cushion thus automatically'built up willalso be automatically maintained for as itspressure tend-sto drop by reason of leakage orany other cause, the check valve4 will liften the back stroke'oif the piston and allowthe passage o--an additional amount of pressure-fluid to theff'or` ward end of the cylinden LThis permits the tool to be' run'. indefinitely on the cushion 115 Without attention. Since thecushioning valve is located between the valve chamber and the-cylinder and at substantially the exit point in the exhaust port from the cylinder,

the clearance space allowed thecushion is-re- '12s; duced. to a minimum. The momentthe piston stai't'son ',its'downward `rnove'nxen't it `.meets a cylinderful. of pressure fluid at'pipe increment of advanceby the-piston. This, vtogether with the-fact that there' isv little or no clearance,'malres it impossible for the pistonto' strike the lower head. y

While I have `herein shown and described 1 30 the same'is not limited to the details of con# lstruct-ion or Vrelative Varrangement of parts,

but that extensivedeviations may be made therefrom without depart-in g from the. spirit thereof.v

VClaims;

1. Inja direcbacting engn'ie,4 `the combination with 'a piston and a cylinder havtworpass'age's leading to one end of fthe e'y ind'er, of au clieelevalv'e in one et said passages adapted toadmit--pressure luid to "andi'estrictthe exhaust from said end et the "cylinde'ig'and means for' cutting o said'cylinder'end fromv lthe exhaust through the 'second passage while opening the cylinder tothe admission'through said-I cheek` valve and the first passagei 2. In a direct-acting engine, the combination'wlth'- a piston and a cylinder having two passages leading 'to one end pf the cylinder,

alnormally inoperative inwardly opening check valve in one of said passages, and means for cutting ofi' said cylinder end from v the exhaust through the second passage,

V while rendering said check-valve operative. i 3. `Ina direct-acting engine the combin-ation with a piston-and cylinder of a valve for alternately admitting pressure-fluid to,

' and exhausting the same from, the .epposite ends of the piston, a normally inoperative check valve, and means for cutting oi'f a cylinderend/from the exhaust while openfI through ing the' cylinder to the admission .the-said check valve. 31

4. In-adireetacting engine, the eombina' tionA witha piston and a cylinder having two passages leading to one endet the piston, of an inwardly opening check-valve, and means whereby one of. said passages .may be Closed and at the same time the,

other opened throughsaidV checlevalve.

' 5. In a directacting engine, the combination with a piston and a cylinder having two ports located `at two different points longitudinally of the cylinder, of an inwardly opening cheek-valve for the .port most remote from the end oi 'the cylinder, and a Amanually operable valve for closing Hthe other port.

. 6. In a direct-actingengine, the combination with a pistonand ya cylinder having.

two ports located-.at two dii'erent points longitudinally of the cylinder, of a normally Vinoperative check-valve for the port mest' remote from the end of the cylinder, and manually operable means for closing the other port and rendering said cheek-Valve operative.

7. In a direct-acting' engine the combination'ywith a cylinder, of a piston, a valve, a port leading to one end of the cylinder and adapted to be connected alternately with the admission and the exhaust through saidv valve, a check valve controlling coimnunicaends'of the-piston, a normally inoperative check valve adapted to a'dmit pressure fluid to and restrict the exliaustfrom vone end of the cylinder, and manually operable means for cutting oft a cylinder end from the exhaust 'andsimultaneouslyrendering said check valve operative.

9..In a direct actingengine, the combination with a piston andcylinder of a valve for alternately admitting pressure fluid to, and exhausting the same from, the opposite ends of the piston, a check valve, and a manuallyl operable valve for cutting oil2 a cylinder end from the exhaust while 'opening the same to the admission through said check valve, said check valve being carried by said manually operable valve.

10. In a direct-acting engine, the combination with a piston and cylinder, of a Valve' for alternately admitting pressure iiuid to, and exhausting the saine from, the opposite ends of the piston,a manually. operable valve for cutting ott onelend oi? the cylinder from the exhaust to form a cushion for the piston when moving in one direction,

and a check valve carried by said manually ,operable valve adapted to open said cylinbination with a piston and cylinder, of a valve for alternately admitting pressure fluid to, andexhaustmg the'same from, the

4'opposite ends of the piston, a manually operable valve provided with passages QS and Q9, and a check valve SO permitting` the entrance of pressure fluid through the passages 28' and 29 into the cylinder end, but cutting off the exhaust of pressure Huid from said cylinder.

12. In a directeacting engine, the combination with a piston and cylinder, of a Vcontrolling valve, a port leading from one end of the cylinder and alternately connected with the vadmission and exhaust spaces through said controlling valve, a check valve opening toward the cylinder space, and a valve provided with `passages for permitting, when in one position, the direct admission of pressure fluid to and exhaust from said cylinder end through said port, and which in another psition cuts off such direct com mnnication and establishes an indirect in-A Ward communicationv between said port' and' cylinder end by Way ofsaid check valve. valve. v A

13. In la direct-acting engine, ,the coinbinationv with a piston and a cylinder having'a' main port and a supplementary porti leading from one end of the cylinder, of a' controlling valve for controlling the admission and exhaust' vto and fromsaidV main port," a cushioning valve provided with a main passage adapted normally to l1permit.

Athe admission of pressure iuid to angl exi-V liaust from the cylinder by Wayof said main port, and provided With a .supplementary passage normally out of register With said main port, manually operable means for Lassie@ moving said valve into vposition to cut oi the valv'e, to admitpressure luid'to but pr vent escape 'of fluid from the cylinder by Way of said supplementary port.

' In testimony whereof, I have signed my name to this specification, in thepresence of A two subscribing Witnesses. y GEO. H:.GLMAN.

1l/Vitnesses t THOMAS B. Boo'rni ROBERT H; KAMMLER.

Images