US2441881A - Hydraulic expansible chamber motor with longitudinally extensible cylinder - Google Patents

Description

May 18, 1948. R R AHAI/S 2,441,881

\ HYDRAULIC EXPANSIBLE CHAMBER MOTOR WITH LONGITUDINALLY EXTENSIBLE CYLINDER 'Filed July 13, 1.945-

Patented May 18, 1948 f artisti UNITED STATES l PATENT UFHCE CHAMBER Mo- TOR "WITH #LONGITUDINALLY EXTENSI- :BLE lc :rLINDEIt Russell'R. Hays, Lawrencdflana ApplicationJuly 13, 1945,s.eria1No.i6o4,9e4 v 1 'Tlisinvention'relatesito'well drilling apparatus and -more particularly tolimprovements in `mechanisms .for l cutting drainage vchannels transversely to-q'a jmain -drill hole; being .in vpart `a continuation of :co-pending application A'Serial lNo. 633,371, for

a vHydraulic drilling device, 'iled/April 29, '1944, now Patent No.f12;388,741,dated 'November T13,

lIn -the 'development `ora small, fexible; :hydraulically -operated drilling tool capable `of 'being turne'd through -a 90angle near lthe bottom of awellbore and of being extended laterallyfor cutting` drainage channels 'inluid bearingstrata the improvements `.made have been of `twobasic types. Since the cutting head 'of Ythevtool 'hasca reciprocating action,fit is evident that the vrate of cutting fmay be increased 5(1) "byincreasing vthe number ioffimpactsl-per'second,:and (2) :by inoreasinglthe intensity of these'impacts. An increase in lthe frequency of the `head'is obtained by 1decreasing the turb 'lence' attendant i'to the passage-.of fluid through fthe engine :and *byK increasing 'the frequency of 'the Valve throwimechanism. -Anincrease in the'throwof the head is obtained by synchronizing the elements responsive to the valve Vfrequencyand designingthem with similar Afrequencies or fmultiples thereof in order-to setup-a stateiof resonance.

A The fmechanical problems involved. @are Ibetter appreciated ^`when it is realizedthat thefengines now b'eingitestedhave anoutside-diameter of one inch,v operate under uid-pressuresiup to;8001# per `sqyinch, are laterally ilexible sufficiently to be zzprojected iithrough a curved :passageway .having av five inch radius, and are capable. otstanding upzunder continuous operation. These-,conditionsfredulre veryugged construction and the eliminationfof' small vsliding parts inthe moving elements since the latter Jhave an `uncanny habit offreezing-.as a result. of tiny particles of labrasive material packing .between them, particularlt whenthe fluidstrearn projected against the face ofthe cutis recycled.v Y y With these considerations in mind, the broad objectives of the Acurrent v'improvements "in "such a hydraulically :operated vdrilling deviceare z,

lfThe provision-cian improved method of mounting an exhaustport valve discupon an adinstable tension valve throwspring to increase its frequency. t 2

r2. Thefprovision-:of ia .Venturi :shaped exhaust port and Venturi shaped chokes in the fluid flow line to :reduce .turbulence of :the -supply stream duringpassagevthroughthe engine.v l

' 13.1, {I'hefprovision -of a pointed rubber lexhaust 4 claims. V(C1. 121-48) valve face capable-of being-driven hydrodynamically into the bell of the exhaust port to `positively close the-port when the axes of the port vand the valve are -net inl alignment.

le. The r'provision kof an auxiliary expansion Vchamber loc-ated behindfthe engine proper, and having the same natural frequency, said chamber being 'actuatedby the :pulsations of the fluid supply column and setting 4up a Vstate of resonance 'whichincreases the stroke `of the-cutting head.

5. 'The provision offan improved cutting head permitting thel-rapidflow of fluid through it and having -spiraled cuttingrteeth so that rotation of the 'head during operation isnot necessary Vincutting a `fullfhole,1said Yhead .also `beingshaped to pass readily 'through a curved passageway.

Ancillary objectives .such as easy assembly and adjustment off'the various parts ofthe engine will rbe made v'clearer .by the `following description taken lin vcon-junction 4witlfi'the accompanying vdrawings in which: Y

Figure 1 is a diagrammatic sketch illustrating `the manner in which ahydraulicengine such as that embodied f' in this invention is extended lat- :erallyffrornawell bore. Y

'Fig '2 lis .an-enlargedelevational view of the engine shown in'Figure 1.

lFig. 3 is a longitudinalsectional view'taken on line III-IIIL-otl'igure 21withparts shown inele- .Vation.- Y

Eig. 4 isla cross .sectional view takenion Vline `VT---LIVof Figure-3. 4

.Referring tothe drawings, `a string of ytubing ILTigure 1, Yis .-.run into a Well'bore l until a footpiece 112 carriedby thetubing -liesrfopposite a i'luid bearing stratum .15, an anchor idextending from the bottom of ythe footpiece1|^2 to the bottom of the well and maintaining Vit vat the desired height. 4A curvedpassagewayiiwithinfthe footpiece iZlis aligned at'its upper Aendwith'the center.v of .the tubing ill, :and 'atyits lower :end opens Iagainstthe :well wall sothat lthe high-pressure hose .IS Kcarrying the flexible drillingengine |78, .floateddown the'insid'e of the tubing -I lafter it and the .well vboreliave'been lle'd with water, is forced :through :the `curved passageway SIS, Yand thus .projected at .right angles tov the iwell' bore for cutting -drainagelate'ral i9 into fluid bearing Vstratumy '1.5.

. ",The zdrillin'g,engineilwhich.is operated bya high-.pressure diuid stream` kcarried iin hose zli, hasfai tempered, toolzsteel .cuttingfhead 2t ofrmore or-,less conical 'form,-the gsurface being grooved to -kforrn Tspiral v.cutting .teeth 22 and yiluideexhaust channels 24 vso Yarranged that -the edges Yof the the water engine is fixed. The upper end of the .Y coiled spring 29 is soldered to the outside of the threaded ring SI, having flange 32 by which it is screwed on the threaded extension 34 of the anged nipple 33. A farther and smaller extension 35 of the nipple 33 projects -downward inside coiled spring 29 and has secured to it bywire-36 the upper end of heavy rubber tube 45 fitting conformably with spring 29 and secured at'its lower end by wire 4'I to the extension 42 of the exhaust port 40 carried inside drill head 20 and seating on shoulder 26,

When the throat 43 of the Venturi shaped exhaust port 40 is closed by valve 60, the inside of rubber tube 45 is seen to comprise ya, closed, longitudinally extensible chamber which is laterally ilexible within the limits of bending of the coiled mainspring 29, thereby permitting its extension through passageway I3, but normally maintaining it in alignment with its initialV direction of travel. The exhaust port valve 60 consists of a resilient rubber capV 51 of conical form screwed onto the threaded extension 59 of the plug 58 carried by the lower end of the valve throw spring 56. The upper end of compression spring 56 passes freely through the inside 50 of extension 350i flanged nipple 33and is xed to the inside ofthreaded ring 54 which screws in- Y side of the couple 33v to Vary the distance the valve 60 is normally held from the exhaust port 40, the hollow locking screw 'I2 serving to maintain it in the desired position.

The resonance chamber 63 which lies between the main Working chamber of the engine I8 and the uid supply hose I6 isV identical with the Working chamber in size and construction but has no valve in its exhaust port. It consists of a coiled spring 62 nxed atits lower end to the outside of threaded ring 6I secured on anged nipple 33, and iixed at its upper end to flanged swivel 64 mounted on shoulder 66 of coupling 65, the upper end of which forms anextension 61 to which the uid supply hose I6 is secured, and the lower end of which forms an extension 68 on which the upper end of rubber extension-tube 'Ill is secured by wire 1I; the lower end of tube 70 being secured by wire 'I4 to the upper extension 'I3 of lock screw 12. Y

In operation the engine described is far more dependable and operable over a wider iiuid pressure range than any of the similar engines tested by reason of the exhaust valve arrangement. This valve is simultaneously responsive to two diiierent dynamic principles. The first of these is that incorporated inthe hydraulic ram and described in detail in said Patent No. 2,388,741. TheV valve 65 being normally spaced or timed so that its nose partially lls the throat of the ex-V haust port 43, acts to accelerate the high pressure fluid stream passing between it and the port 43 with a subsequent decrease in pressure which creates a hydrodynamic forceacting to positively seat the valve 60 in the port against the tension exerted by4 the `valve throw spring 56. With closing of the exhaust port, the fluid stream decelerates creating a shock wave, and subsequently the pressure in the line decreases to normal line pressure, whereupon the tension of the spring 56 pulls the valve 60 from port 43 to open it, thereby permitting acceleration of the uid stream and repeatingthecycle.

The pertinent distinction between the exhaust valvesroperation at this time and later resides in the fact that movement of the drill head and hlongitudinal expansion of the engine chamber 46 is not essential to its operation. Hence, even -if the drill head 20 -be stuck, the valve continues to operate and lafforce of considerable magnitude set up :through pulsation of the iiuid supply sftrean'imis` available to loosen it. With normal operation, however, the effect of closing the exhaustport 43 is to cause the accelerated fluid streamgto exert its energy in extending the expansion Achamber 46 against the tension of the mainspring 29 and thus drive the drill head 2li downward. Since the port 43 carries the valve 60' withit, this movement acts to increase the throw tension of spring 56, with the result that it throws quicker and farther fromthe exhaust port than would be the 4case were the position of the Vdrill head 20 fixed.; This increased opening of the port 43 acts in turn` toY permit more rapid emptying of expansion chamber,V 46 through the contraction tension of the encircling mainspring 29p1aced under tension. during its expansion and further-acts to permit movement of a larger mass of ,fluid through the port in a givenperiod, thereby increasing the hydrodynamic force; originally available to close the valve 60 again;

From the standpoint of dependable and continuous operation, this valve arrangement is further advantageous in that iineradjustment of the tension ofthe valve throw spring 56 is not essential to its operation. This arises from the fact that if the valve 60 closes the port 43 initially (and it normally does so -at fluid pressures below the normal operating range), the hydrostatic head acts to extend the expansion chamber 46 until the exhaustport 43 carried by it is pulled far enough away from the valve 60 to set it into operation. Since the hydrostatic head exerts a` force lof considerable magnitude, this makes the enginedifiicult to kill through a wide range of feeding pressures, too rapid feeding of the supply'hose into the cut giving rise to a bucking action of the engine .during which it throws itself clear of the cut instead of dying.

A further advantage of this rugged valve actionV lies inthe fact that it will .take off when the engine is twisted laterally. Even so, the engine would not functionY properly were it not for the resilient nature of the exhaust valve 60 and the fact thatits tapered shape permits it seating in the belled throat ofthe exhaust port 43 even when not in alignmentu with the port. Many different types ranging fromball to needle valves were tried before the 'shape'.shown and made of vulcanized innertuberrubber Vwas developted, VThis valve andthe use of-a valve spring 56 having thel Vsame frequency as the mainspring 29 but a smaller amplitude, used in conjunction with an expansion chamber 46 having a similar fluid frequency are the essentialelementsin obtainingcontinuous operation of the engine.- Since 'a water engine operated by the elements shown and described, is capable 0f Wide adaptation for 'use where space requirements prevent the adaptation of more convventional types of hydraulic engines, what is claimed is:

1. In a hydraulic engine, a fluid pressure supply conduit, a coupling, a longitudinally extensible, tension contractable cylinder carried by and communicating with said conduit through said coupling, a head carried by said cylinder having an outlet port for said cylinder, a valve for said port inside of said cylinder, a valve throw spring xed to said coupling and carrying said valve, said spring normally urging said valve to an open position with vrespect to said port, hydraulic means urging said valve to a closed position with respect to said port, said hydraulic means being stronger than said spring tension means when said cylinder is contracted, andsaid spring tension means being stronger than said hydraulic means wh'en said cylinder is extended, whereby said valve closes said port when said cylinder is contracted and opens said port when said cylinder is extended thereby intermittenly varying the uid pressure inside of said cylinder to cause reclprocation of said head.

2. In a hydraulic engine, a fluid pressure supply conduit, a coupling, la longitudinally extensible, tension contractable cylinder carried by and communicating with said conduit through said coupling, a head carried by said cylinder having an outlet port for said cylinder, a valve for said port inside of said cylinder, a valve throw spring having a smaller operating amplitude than the operating amplitude of said cylinder adjustably xed to said coupling and carrying said valve,

l outlet port for said cylinder, -a valve for said port said spring normally urging said valve to an open position with respect to said port, hydraulic means urging said valve to a closed position with' respect to said port, said hydraulic means being stronger than said spring tension means when said cylinder is contracted, and said spring tension means being stronger than said hydraulic means when said cylinder is extended, whereby said valve closes said port when said cylinder is contracted and opens said port when said cylinder is extended thereby intermittently varying the uid pressure inside of said cylinder to cause reciprocation of said head.

3. In a hydraulic engine, a tension contractable cylinder, a traveling exhaust port, and exhaust valve hydraulically closing said port and tension inside of said cylinder, a valve throw spring having a frequency substantially that of said cylinder but smaller operating amplitude than the operating amplitude of said cylinder adjustably fixed to said coupling and carrying said valve, said spring normally urging said valve to an open position with' respect to said port, hydraulic means urging said valve to Ia closed position with respect to said port, said hydraulic means being stronger than said spring tension means when said cylinder is contracted, and said spring tension means being stronger than said hydraulic means when said cylinder is extended, whereby said Valve closes said port when said cylinder is contracted and opens said port when said cylinder is extended thereby intermittently varying the fluid pressure inside of said cylinder to cause reciprocation of said head. A

RUSSELL R. HAYS.

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

UNITED STATES PATENTS Number Name Date 42,979 Welham May 31, 1864 2,098,886 Saiord Nov. 9, 1937 2,239,298 Kraut Apr. 22, 1941 2,345,816 Hays Apr, 4, 1944 2,359,147 Merten Sept. 26, 1944 2,388,741 Hays Nov, 13, 1945 2,390,646 Hays Dec. 1l, 1945 FOREIGN PATENTS Number Country Date 333,276 Germany Feb. 21, 1921

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