US2491059A - Hydraulic turbine - Google Patents

Description

Dec. 13, 1949 lJ, ,RlNG 2,491,059

HYDRAULIC TURBINE Filed Aug; .29, 1945 feo@ MWA Patented Dec. 13, 1949 HYDRAULIC TURBINE Joseph J. Ring, Wauwatosa, Wis., assgnor to Allis-Chalmers Manufacturing Company, Milwaukee, Wis., a corporation of Delaware 'Application August 29, 1945, serial No. 613,381 t The present invention relates generally to improvements in hydraulic turbines and relates more particularly to improvements in the control and operation of hydraulic turbines of the impulse type.

Considerable difficulty has heretofore. been experienced in controlling the supply of operating fluid to impulse turbine runners responsive to load conditions thereon. The operating fluid is generally supplied to the runners of impulse turbines through a long pipe line and under an eX- tremely high pressure. It is, therefore, .highly impractical to utilize a quick acting valve for controlling the amount of fluid delivered to the turbine runner in accordance with variations in load upon the turbine because of the imminent danger of bursting the pipe line when rapid changes in the velocity of the flowing fluid within the pipe line are effected. Since sudden variations in the load on a turbine of this type are frequent, it is extremely dangerous to attempt sulciently rapid closing of the valve in the supply pipe or nozzle to maintain the speed of therunner constant.

To eliminate the obvious disadvantages attendant the use of quick acting valves in the fluid supply lines of impulse turbines, it has heretofore been common practice to permit the operating fluid to issue from the nozzle at a constant rate, compensating for changes in load by deflecting more or less of the operating fluid from the buckets or blades of the runner. This deflection of a portion of the stream of operating fluid may be effected either by means of a movable nozzle which may be tilted toward or away from the buckets to change the directionof fluid flow, or by means of a separate deflector element having a hood or the like which may be moved into or out of the path of the operating fluid to deflect more or less of the fluid away from the buckets. In such installations, the fluid deflected from the buckets is wasted and performs no useful function, thereby undesirably depleting the fluid supply in the main reservoir.

To substantially reduce the large amounts of uid wasted through the use of devices of the type hereinabove described, it has also been heretofore proposed to provide a combination of quick acting fluid deflector and relatively slow acting valve means for controlling the amount of fluid issuing from the nozzle. Such devices are likewise of two types, one type being provided with a movable nozzle for quickly deflecting the stream of operating fluid and with a needle valve for more slowly controlling the ilow of fluid through the 4 Claims. (Cl. 253-24) for quickly deflecting the stream or jet and with a needle valve for subsequently slowly controlling the flow of fluid through the nozzle. Many systems for synchronously controlling the operation of the jet deecting means and the needle valve means of these prior art assemblages have heretofore been'proposed. However, in the past, considerable difficulty has been encountered in providing a simple and universally applicable system for controlling the operation of the jet deflecting and needle valve meansin complete synchronism and without considerable undesirable fluctuation in the speed of the wheel or runner during adjustment of the deflector and needle valve to a new position.

It is therefore an object of the present invention to provide an improved system for automatically controlling the supply of operating uid to the runner of an impulse turbine which obviates the objectionable features of prior systems and devices.

Another object of the present invention is to provide an improved control system for synchronously operating the jet deflector and needle valve of an impulse turbine responsive to variations in load on the turbine.

Another object of my invention is to provide an improved hydraulic impulse turbine having a jet deector and a needle for controlling flow of fluid through the nozzle with means for automatically controlling the operation of the ,iet deiiector and needle in synchronism through the expedient of a single simple relay servomotor and standard speed governor. p

Another object of the invention is to provide an improved hydraulic impulse turbine having a jet dei'lector and a needle for controlling flow oi `fluid through the nozzle with means for quickly taneously but more slowly moving the needle to the needle, a deflector movable into and out of the- 2 nozzle, and the other type being provided with a separate deflector including a hood or the likev path of the fluid, a governor, means operatively connecting the governor with the deflector for moving the deector directly in response to changes in load, means for simultaneously operating the pilot valve of the servomotor to effect adjustments in the position of the needle, and means directly responsive to the movement of the needle for moving the deector to a position just out of the` path ofthe fluid foreach adjustmentV of the needle.

A further object of this invention is to providean improved governing system for hydraulic turbines of the impulse type which is simple; durable and inexpensive in construction and which is highly efcient and economicaliiin'operation.

Additional objects and advantagesofftliefpresent invention will be apparent from the following detailed description.

A clear conception of one embodiinentwof the present improvement and of the mode of constructing and of utilizing apparatus. built in accordancewith my inventionmaybehad by referr-ing to the drawing accompamfing andf'ormingA a part of this specification wherein-the; various parts are referred; to` by'suitable: reference', characters;

The single ligure shown inthe drawing is a verticalV section throughA a hydraulic turbine of" thel impulse` type embodying; the' features of'my present improvement:

Referring to the drawing', the. reference numeral'5designates the impulse wheel orrunner generally; The runner' may be of'we'll known construction, consisting ora' disc Bkeyedto the and providedwith a plurality'of buckets.

or blades B suitablymounted'at spaced. intervals around theperiphery thereof.

The runner 5 isdrivenby a jet or stream.. off' waterf'under pressure delivered" from a suitable` source of. supplyv (not shown)' by way of. a pipe land issuing, as. indicatedby dotand 'dash lines, fromthe discharge orifice: I2L'ofa stationary-nozzle I 'l against the buckets 8v of the runner. An axially movable needle valve I3 for forming'tlie operatinggjet and'regulating the quantity of water` delivered from the. nozzle to the runner is provided within the nozzle II; -The amount' ofi water deliveredby the nozzle is controlled'lby the. position of the needle as will be hereinafter. more fully described.

The needlevalve I3 is carriedlby astem. I5,se. curedat thev end thereof` to a pistonlpperating. ina. hydraulic cylinder. I 1, suitable packingsl', IB, respectively. beingprovidedbetween thestem. I 5.', and nozzle Il andthe.stemlandcylinder. I.'I.l To actuate the piston I6, the fluid under. pressure. is .admitted to, and. discharged. from.. the.- front and rear. portions Vof thecylind'er inawell known y.

manner. byl way of pipes 2l, 22, respectively.. Fluid iiow to the cylinder ITI throughthe pipes` 2.I, 22. is controlledby-a pilot valve 2:3 working. within a cylinder 24 to openandclosethecutlet ports 26, 21 of the. cylinder. 2 4, whiclrports-corn-` municate with. the. pipes. 2l, 22, respectively. Fluid under pressure is suppliedv to the cylinder 24,byfway` of pipe 28v froma suitable source (not, shown), andthe` opposite. ends ofthe cylinder 24 are suitably vented-as.-by'pipesi23, Sr'to permit:escape of fluid displaced in the cylindery Il during movement ofthe pistonI 6;

Inzaddition to the needle valve I3for regulating-,the jet issuing from the nozzle] I a -deector 32 isfprovided. Asshown, the. deector. 32.comprisesa hoodor. deiector plate 33,carried.by an arm or arms 34 mounted .on a rockshaft 35'wbich,

in turn, is supported by one or more lugs 36 suitably formed on the nozzle I I adjacent the discharge end thereof. As will hereinafter more clearly appear, the deflector 32 is swingable into the jet issuing from the nozzle II to deflect portions thereof from the buckets 8 of the impulse Wheel until such time as the needle valve i3 may be moved to the new position of adjustment.

Movement of the needle valve I3 and deflector 32l is controlled by a governor 38, shown herein as being of the yball type but which may be of any known construction. The governor 38 is suitably driven, through mechanical or electrical connections, in accordance with the speed of the runnerrS'. As-herein illustrated, the governor is connectedeto ailoati'ng lever 4G pivotally attached at one end (left) thereof to the stem of a pilot valve SS'Loperatingina cylinder 4I to control the passage-of. fluid under pressure, supplied by a pipe 43' from a suitable source (not shown), through pipes 44, 45 leading to. opposite ends of a cylinder 41:" 'having' a' Ypiston 47' provided therein. The pilot valve' cylinder-41 is also vented atA opposite ends', asby pipes 49, Ailllito permit escape of uid displaced in the servomotor cylinder 46 during movement of the piston 4'I as will hereinafterm'OT Clearly appeal'.

The: piston 4T carries a' rodV 5I` extending;

through' an end wall. of the' cylinder 46, suitable o packing being-provided betweenthe end wall and the axially movable rodi The rod 5I is'` concrank arm 56. mounted thereon forming a bell crank. The crank'arm 56 is, in turn, connected by av link.5"I to, a compensator device 59 which.

relays themotion of the piston rod 5I to the opposite end (right) of theoating lever 4U in the usual' manner to return the pilot valve 39` toi neutral position.

Therod' 5I is further connected, by a link`52; to` a crank arm. Ifl mounted ona rockshaft 6I which also hasan arm.62 secured theretoto form` aY bell crank; A rod64 connects the crank arm 62.with a crank arm 65 securedto a rockshaftl which has crank arms 6?,.68 secured'thereto to.

likewise form a bell'crank..

The crankarm EllcarriesV a rod I which is,

the. speedof. the impulse wheel 5. is relayed,.by way'ofpilot valve 39 and associated mechanism,

to.tl:ie.servon1otorE 4B,` 4'I and tothe deiiector 32' through the. described mechanical connections including bell crank 50, 62,'.connecting rod 64,

bell, crank. 65, 68; rod, '1(3,v lever. "I2, connecting` rodl5, and bell crank 75, 34.'.

To. communicate such speed changes to. the,

needle valve I3, the crank arm 6`I.is connected, by way of a rod 71, to one end'of a lever 7S pivotally mounted .at 86 on a fixed support SI. lever. '18. is connected at its opposite end by a link 82,` tol one end of a floating lever 83' which. is'pivoted atv the opposite end thereof on a roller Y 86 andis connected; intermediate its ends, to the stem 842 of the pilot valve 23.' Thus, as the bell crank..65`,.6.1rotates, responsive. to. changes .in the speedf thewheel 5. relayed; from the governor, suchchangesareobviouslyrelayed by way ofrod '11,.lever I8,.linkage 82, andlever 83 to the pilot It is thus apparent ,that'any change recorded by the. governor 3B.in

The,

valve 23 which controls the hydraulic pressure supply to servomotor cylinder I1 for actuating the piston I6 which carries the valve stem I5, thereby adjusting the needle valve I3 to a new position.

To restore the pilot valve 23 to neutral position as the needle valve I3 is moved the distance necessary to eiect the demanded jet adjustment, a cam 81 carrying the roller 86 oi the floating lever 83 is provided. The cam 81 is formed on one end of a lever 88 pivotally mounted at 89 on a iixed support 90, and the opposite end of the lever 88 is connected, by a link 52 or the like, to an arm 93 carried by the valve stem I5. Therefore, as the valve stem I5 of the valve I3 is moved by the piston 23, the arm 93 is carried therewith, thereby causing the lever 88, through linkage 92, to rotate the cam 81. As the cam 81 is rotated, the roller 86 is moved over the cam surface, thereby causing the floating lever 83- to likewise follow the movement thereof to restore the valve 23 to neutral position whereby further movement of the piston I6 and needle valve I3 is stopped by closing oil the fluid supply to the cylinder I1.

As the needle valve I3 is moved by hydraulic pressure to its new position of adjustment, the deector is simultaneously caused to move to a position whereby the hood 33 is stopped just outside of the jet upon completion of movement of the valve I3. This movement of the deector is caused by rotation of the floating lever 12 around the pivot 1I as the lever is carried, by reason of its pivotal connection, with the valve stem I5, such movement being relayed to the deflector 32 through rod 15 and crank arms 16, 34.

The shape of the cam 81 and the relationship of the levers and movements are such that there is a position of the deector 32 whereby the hood 33` thereof is just outside of the path of the jet for each position of adjustment of the needle valve I3, and there is likewise a xed position for the bell crank l(i5, 68 and the pivot pin 1I for each load imposed on the governor 38 whereby the improved device will reduce the jet to the proper size and simultaneously move the deflector hood 33 to a point just outside of the path of the jet.

From the foregoing it will now be evident deflector means 32 movable toward and away l from the` stream, a control means has been`provided for restoring the speed of the wheel to a selected value by positioning the deilector means and the needle in response to change of speed upon change to a given load on the wheel. This control means comprises the following principal elements: a control member, which may be taken as the rod 5I, along with means, here shown as including a servo-motor piston 41, adapted to move the control member 5I to a position predetermined by the load on the wheel and the selected value of speed at which it is desired that the wheel shall rotate; iiyballs 38, which control the position of the control member 5I is reflected in a temporary change in the position of the flyballs and such change in position causes the control member 5I to assume a predetermined new position; actuating means for the needle I3, which is here shown as provided A change in load on the wheel s by a servo-motor including a pilot valve 23, any suitable connection, such as the linkage extending from the control member 5I to the pilot valve 23, providing means whereby the needle actuating means is caused to adjust the needle to a position which depends on the position of the member 5I; and means dependent upon the position of the control member 5I and dependent upon the position of the needle I3 for positioning the deiiector means 32, this means being here shown as including a link 18, a lever 12, and a link 15. While the principal elements of the control means have been identified in the particular embodiment shown in the drawing, it will be understood that this has been done by way of explanation with respect to the illustrated embodiment and not by way of limitation since those skilled in the art will understand that the invention may assume other embodiments. The operation of the invention will now be considered in detail with reference to the illustrated embodiment.

In describing the operation of the improved device, all of the parts of which are shown in the drawing as being in neutral position indicative of no load change, let us assume that there is a drop or reduction in load on the turbine. As the load on the turbine drops, the speed at which the runner 5 is driven by the jet issuing from thenozzle II increases; and this increase in speed of the runner is transmitted to the governor 38 in a well known manner, causing the flyballs to move outwardly by centrifugal force against the restraining action of their spring. As the governor thus responds to the increase in speed of the runner, the pilot valve 39, by reason of the connection of its stem with the left hand end of floating lever 40, is caused to be lowered within the cylinder 4I, thereby opening the passage and right side of the cylinder 46 to uid pressure supplied by way of pipe 43 and opening passage 44 and left side of cylinder 45 to vent pipe 49. As the pressure within the passage 45 and right side of cylinder 46 builds up, the piston 41 and its rod/ 5I are moved to the left, causing the crank arms 60, B2 and rockshaft 6I to rotate in a counterclockwise direction to move the connecting rod 54 downward while simultaneously causing the crank arms 54, 5-6 and rockshaft 55 to rotate in a clockwise direction to restore the pilot valve 39 to neutral position through the connection of the compensator device 59 with the floating lever 40.

As the rod 64 is moved downward, it causes the crank arms 65, 61, 68 and rockshaft S5 to rotate in a counterclockwise direction. As the crank arm 68 is thus rotated, the movement thereof is in turn relayed, by rod 10, to the floating power lever 12 which is rocked to the left about its pivot 13, thereby likewise moving the rod 15 to the left to rotate the crank arm 15, rockshaft 35, and crank arm 34 of the deflector 32 in a clockwise direction, the deiiector hood 33 being carried quickly into the jet by the arm 34. The movement of the delector hood 33 into the jet, as hereinabove described, continues until a suicient amount of water is being deilected from the buckets 8 to regulate the runner to the reduced load, whereupon the speed of the wheel will be restored to normal and the governor will stop the movement of the rod 64, thereby holding the crank arms 65, 61, 63 and the rod 10 and pivot 1I stationary.

Upon counterclockwise rotation of the crankV port 21, passage 22 and right side of servo- 10 motor cylinder IT are opened to fluid pressure suppliedby way of pipe 28, and the port 25, passage 2i and left side of cylinder Il' are opened to vent pipe 29. sage 22 and right side of cylinder II builds up, the piston I6 slowly advances to the left within the cylinder, carrying the valve stem needle valve I3 therewith to gradually reduce the size of the jet issuing from the orifice I2. of thc-'nozzle II.

As the stem I5 of the needle valve is moved to the left, it carries the pivot pin i3 with it, thereby rotating the lever 'I2 counterclockwise about the pivot 1i. This rotation of the lever 'I2 about the pivot H moves the deector hood 33, through rod 'I and crank arms 16, 34, slowly in a counterclockwise direction to a, point just outsideof the path of the jet as shownv in the drawing, whereupon movement of the needle valve I3 and deflector 32 is stopped, as will be hereinafter more fully described, with the jet reduced to correspond with the changed load requirement of the turbine.

During movement of the needle valve as hereinabove described, the stem I5 also carries the arm 93 to the left, thereby rotating the lever 88, through linkage 92, in a clockwise direction about the iixed pivot 89` and causing the cam B7 to raise the roller Sli-and floating lever 83. As the lever 83 is thus raised, valve 23 is likewise lifted in cylinder 24 until it is restored to its neutral position, as shown, closing off the ports 25, 2'I and passagesy 2|, 22, thereby stopping movement of the piston IB and needle valve I3 as well as the deector 32. The adjustment of the jet issuing from nozzle II to correspond with the reduction in load on the turbine is thus completed and the various parts are retained in neutral position until again called up by the governor to eiect a new adjustment for a change in load.

I f there is a load increase on the turbinethe reverse sequence of operation obviously occurs, pilot. valve 39 being raised to admit fluid under pressure to the leftside of servomotor-cylinderA 46, thereby moving the 'pistonv 41 to the right until stopped by restoration of the pilot valve, through action of the compensator device 59 and floating lever 40, to neutralposition. Movement of the piston 4l and rod 5| to the right rotates crank arms 80, 62 clockwiseto raise the` rod B4, rotating the crank arms 55, 6T, 68 clockwise. As crank arm 68 rotates, rod 1G, lever'l2 and rod 'I5 are moved to the right torotate'the crank arms 75, 34' counterclockwise, thereby immediately quickly moving the defiector away from the jet. of crank arm `68,' crank arm 6'!Y rotates and moves rod 11 downward, thereby raising the right hand end of floating lever 83 to lift pilot valve 23 and admit fluid under pressure to the left side of servomotor cylinder l1. As pressure builds up in the lefteside of cylinder I1,

Simultaneously with the rotation 523 16, 34, to a position such that the hood 33v is just As the pressure'in the pasoutside of the path of the increased jet and likewise simultaneously rotating the lever 88v and cam'B'I, through link 92 and arm 93, coun- `.terclockwise the roller 86 and oating lever 83, thereby restoringr the valve 23 to neutral position and stopping movement of the piston I6, needle valve I3` and deector 32.

From the foregoing detailed description, it is Vapparent that, the present invention provides an 5 improved system for controlling the operation and performance of hydraulic impulse turbines wherein the operation of the several partsis completely automatic and directly responsive and proportionate to changes in load placed upon the turbine with minimum wasteof water during adjustments. It isto be noted that the governor responds toevery change in speed of the runner and, through servomotor- 46, 4T and the described mechanical connections, relays these changes directly to the jet deector to move the deiiector quickly into or away from the operating jet a distance proportionate to the changed load. As load changes are relayed from the governor to the jet deflector, the pivot II is moved to and held in a new position such as will insure return movement of the deilector to neutral position with the deflectorA hood just out of the path of the jet after complete adjustment thereof to the 5 changed load. Simultaneously with the initial rapid movement ofthe deflector, movement of' operated in complete synchronism through the expedient of a single standard-speed responsive governor and simple relay servomotor. The improved control mechanism is simple and durable in construction and operation and has a minimum number of `parts which are all readily accessible for repair, adjustment or replacement; and hydraulic turbines embodying the invention are highly ecient and economical in operation. Obviously, although one form of governor has been diagrammatically illustrated and described in conjunction with the improved system, other known types of governors may likewise be utilized therewith without departing from the invention. Similarly, the various rods, cranks, levers and links may be rearranged and reduced or increased in numbers to suit the particular requirements attendant each installation.

It should therefore be understood that it is not L 5 desired to limitk the. present invention to the exact details of construction and mode of opera- Patent:

1. In combination with a hydraulic impulse wheel, a. nozzle for directing a stream of fluidi against said Wheel, a needle for controlling the t ow of fluid through said nozzle, deector means movable toward and away from said stream, and control means for restoring the speed of said wheel to a selected value by positioning said detlector means and said needle in response to change of speed upon change to a given load on said wheel, said control means comprising: a control member; a servo-motor having a pilot Valve, for moving said control member; means responsive to tne speed of said wheel; means wnereby said speed responsive means and said servo-motor act jointly to position said pilot valve to cause said servo-motor 'to move said control member to and leave it in a predetermined diiierent position in response to change from and restoration to said selected speed; a second servo-motor ior moving said needle; means wliereby said second servo-motor is caused to adjust said needle to a position dependent upon tile position of said control member, to

tlie position o1' said control member and dependent upon tlie position ol said needle iol' positioning said deiiectoi' means.

2. ln combination with a nydl'aulic impulse wheel, a nozzle :or directing a stream ol nuid against Said WIIESJ., al IleClie OL COlIf/fillng i'l'd now oi nuid tnrodgn said nozzle, delleotor means movable toward alld away iroiii said sti-calli, aild control means lor restoring the Speed of said wneei to a selected value by positioning said dei'iector means and said needle in response to c'llange oi speed upon change to a given load on said wheel, sald control means comprising: a control meirlber; a servo-motor naviiig a pilot valve, for moving said control member; means responsive to the speed oi said wneel; means wrlereoy said speed responsive means and said servo-motor act jointly to position said pilot valve to cause said servo-motor to move said control member to and leave it in a predetermined dilierent position in response to change ii'om and restoration to said selected speed; a second servo-motor having a pilot valve, i'or moving said needle; means whereby said pilot valve or sa-d second servomotor is initially positively moved to a position dependent upon the position of said control member; means, acting on the pilot valve oi' said second servo-motor, responsive to the movement of said needle, to cause said second servo-motor to adjust said needle to a position dependent upon the position oi said control member, to adjust said stream; and means dependent upon the position of said control member and dependent upon the position of said needle for positioning said deflector means.

3. In combination with a hydraulic impulse Wheel, a nozzle for directing a stream of fluid against said wheel, a needle for controlling the flow of fluid through said nozzle, deilector means movable toward and away from said stream, and control means for restoring the speed of said wheel to a selected value by positioning said deector means and said needle in response to change of speed upon change to a given load on said wheel, said control means comprising: a control member; a servo-motor having a pilot valve, for moving said control member; means responsive to the speed of said Wheel; means whereby said speed responsive means and said servo-motor act jointly to position said pilot valve to cause said servo-motor to move said control member to and leave it in a predetermined diil'erent position lil response to change irom and restoration to said selected speed; a second servo-motor having a pilot valve, Ior moving said needle; means wnereby said pilot valve 0i said second servomotor is initially positively moved to a position dependent upon tile position oi said control member; means, acting on the pilot valve of said second servo-motor, responsive to the movement oi said needle, to cause said second servo-motor to adj ust said needle to a position dependent upon tile position of said control member, to adjust said stream; and means constructed and arranged initially to move said deiiector means in a given direction in response to movement of said control memoer and tnen to move said deliector means in the opposite direction to a position dependent upon tne position oi said control member and dependent upon tile-position oisaid needle.

4. In combination with a hydraulic impulse wheel, a nozzle ior directing a stream oi' Iluid against said wheel, a needle for controlling the iiow of iluld through said nozzle, deriector means movable toward and away i'rom said stieam, and control means iol' restoring` the speed oi' said wheel to a selected value by positioning said deiiec'tor means and said needle in response to cllange ol speed upon change to a given load on said wheel, said control means comprising: a control member; a servo-motor havilig a pilot valve, iol moving said control member; means responsive to the speed oi said Wheel; means wnereoy said speed responsive means and said servo-motor act jointly to position said pilot valve to cause said servo-motor to move said control member to and leave it in a predetermined different position in response to change i'rom and restoration to said selected speed; means positively connecting said control member with said denector means to move said deiiector means in a given direction in response to given movement oI said control member; a second servomotor having a pilot valve, for moving said needle; means whereby said pilot valve is ini'- tially moved to a position dependent upon the position oi said control member; means, acting on the pilot valve of said second servo-motor, responsive to movement of said needle, to cause said second servo-motor to adjust said needle to a position dependent upon the position of said control member, to adjust said stream; and means whereby said adjustment of said needle moves said defiector means in a direction opposite from said given direction.

JOSEPH J. RING.

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

UNITED STATES PATENTS Number Name Date 870,291 Henry Nov. 5, 1907 993,064 Henry May 23, 1911 1,131,344 Dufour Mar. 9, 1915 1,706,812 Pfau Mar. 26, 1929 1,914,679 White June 20, 1933 2,158,108 Deglon May 16, 1939

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