US825999A - Governing mechanism for turbines. - Google Patents

Description

PATENTED JULY'1'7, 1906. J. WILKINSON.

GOVERNING MECHANISM FOR TURBINES.

APPLIOAIION FILED NOV. 2. 1905.

2 SHEETS-SHEET l No. 825,999. I PATENTED JULY 17, 1906'.

J. WILKINSON. GOVERNING MECHANISM FOR TURBINES.

APPLIOATION FILED NOV, 2. 1905.

2 SHEETS-SHEET 2 mm I I gawentoz To all whom it may concern:v

.. UNITED STATEZAlENT OFF-1013p "JAMES WILKINSON, or PROVIDENCE, 'Rnonn ISLAND,- Ass-ieiion ro .w nn nson'rossmn COMPANY,

n eaaeoa Be it "known" that I. JAMEs WILKINSON, a citizenof the United States. residing at Providence,'-in the county of Providence and State I of Rhode Island, have in ented new and useful Improvements in Governing Mechanism for Turbines of which the following is a specific'ation. I

" My invention relates to an improvement in "controller mechanism for fluid-motors, and

particularly elastic-fluid turbines, and has for its object to perfect in its simplest and most efficient form a safety valving and auxiliary governin means'for the motor.

Thesa ety-valve means new in general use 7 .are such as operate only under abnormal conditions. They may be operated automatically by the pressure, tripped by the governor, or brought into service by devices which 0 crate under predetermined conditions. ll

fsuch safety-valve means are unreliable for the reason that they operate only at long in tervals, and there is no means of indicating at any given time whether they have not stuck or become otherwise inoperative. No valve that is not continually exercised should be solely relied upon for safety purposes. An-

other objection to these constructionsis that the valves have to be reset after they have operated. Also the unbalanced conditions under which the valves operate frequently causes the valve to be injuredduring its opening or closing movements, requiring it to be made ofunnecessary strength and weight.-

"It is the'purpose of myinvention to obviate the above disadvantages by the provisionof what may be broadly termed an active safety-valve, which i functions, responsive to speed or'loadconditi'ons, as a secondary controller means.

Considered more specifically, my invention maybe said to comprise a safety-valve means which operates on the main supply to the tur-' i him in "conjunction 'with prim'arygovernoradmission of the motor fluid to the turbine,

controlled valve means, which regulate the both valve means operating independently and moving responsive to speed conditions, being preferably controlled by the same speed governor. Y The desired results are best-obtained where one orbotli of the valvemeans are operated by a relay power controlled by the governor, asthis' takes the work directly -A CORPORATION OF ALABAMA GOVERNING iviEcHAmsm FOR TuRB|NEs. I

Specification of Letters Patent.

. Application filed November 2, 1905- Serial No. 285,622.

Patented mang to assume control of the :turbineimthe of injury to the other. In. otheljiwpllds'irthe active speed-responsive.safety-valve; consti tutes a secondary controller 'meansfits mjr'iver ments (being so correlated 'with fthatofathe valve or valves of the primary?con ltollfer means for the turbine nozzles: that'iithacts without any controllingorwiredrawing'effect ofi the governor and enables;oneEvelyn niaii 4 even on the fluid-supply to.the.turbine,orr,tothe .1.

turbine-nozzles so long. as the nozzle-ivalves move properlyin res onseito governor orload conditions; but in t e event thatxthe-nozzlevalves, by reason of injury or defect,- attem t to admit a greater volume of fluid thamt e independently of .-.the

means and .the safety-valVeare operatedwby g g a relay power regulated by the samegovernor and in the other of which the safety valve is direct connected to the governor; whilithe controller means are operatedthroug'hncrelay-power means. If a siepaiatejxspeilnfora; load-responsive devicewereprovidedafonsop crating the controller and 'safetysvalve means,

they could be direct connected but. thisds-an unnecessary complication; in.

3 My invention also proposes ito .C0 Ver,.g; broadly, the novel combinationwith-amiub tinozzle turbine of a doubleacontrollersmeans, one acting independently of-the other totcnntrol the open ng and closing ,of the' isewei'al supply-nozzles, preferably without .wiiedizaw-r 'ing, and the other acting. upongthe supply of motorfluid to the nozzlesand operaaniinggnm der normal condition without-"eflfect au ,"on

the supply, but undc 'abnornral conditlons functioning as a safety+valve-by=. a ssnmin f wiredrawing control of the turbinesiipp y. Though controlled bya-rspeederesponsive-device, I-pro ose to sofadapft thetioperating means fort e safety-valve;that'ijt'willlautomatically close upon breakage oirtlre I responsive device or its connections With.

' My invention further Se s-"the details of construction and combination of parts hereinafter more particularly described, but is claimed without specific limitation thereto.

Referring to the drawings, Figure 1 is a side elevation of the turbine broken ma to show the primary and secondary governing means in section. Fig. 2 is a similar view of a modification of my invention in which one of the valve means is direct connected 'to the governor.

Similar reference-numerals refer to similar parts in both drawings.

I According to the drawings I have illustrated my invention as applied to a turbine of the horizontal axial flow type comprising a supply head 1 and a plurality of diaphragms 2, subdividing the interor of the turbine into stage-compartments, within which. bucket-wheels 3 rotate.

. being operated by a stem 11, connected-to a spider 12 in the valve, which is in the form of a cylidrica-l' shell through which pressure passes from port 8 through shell ports into the steam-chest 5. The stem 11 for operat- 'ing the valve passes through an elongated packing-sleeve 13, formed integral with aplate '14, which closes an end of the valveshe'll, being held between the-flanges 15 of the casin 7 and the flanges 16 on a cylinder 17 said anges being connected by bolts or rivets. This stern unbalances the valve so that the'supwly-pr-essure tends to close it. A piszon '18 tlns cylinder is connected to the stem 1 and is acted upon by a coil-spring 1'9, tending to move it in the direction to close the valve .10. Pressure is admitted through a passage 20, leading from a controller-chamber 21 to the cylinder to move the piston against the spring 19 and the pressure acting on the valve-stem 11 I admit the 'supply'pressure to this controller-chamfber 21-bya passage 22, leadin from casing 7 through the plate 14 and cyhnder 17 into a circular valve-chamber 23, from which the ess'ure is discharged throu h a port 24 and j jet-nozzle'25 into 'the'cham or 21 and pasoperatively connected to a'crank 28,

sage 20. To vary the impact effect of the jet in the passage 20, I provide means to throttle the jet, such as a rotary valve 27, which {is substantiallysemicylindrical in shape and w ich in turn is adjustably connected to a rod 29, op-

A shell 4- surrounds the diaphragms -and head,.a1id is is driven in any desired manner from'the. (main turbine-shaft 36. The'bearing 34 is mounted on the bearing 37 for the turbineshaft. A'passage 38 leads from the chamber 2'1 and conducts thejet fluid into the turbine or to any other desired point of usefulness.

, A port 39 admits the at-mo'sphere behind the piston 18. As the governor moves respon- -sive to speed changesit adjusts the valve 27 to throttle the j et-nozzle 25, thereby .varyin the impact action of the jet in the end 0 cylinder 17. This produces a variable static pressure in the end of the cylinder which acts against the unbalanced condition of the'valve' 1 controlling-pressure rises or falls the piston will be adjusted to various intermediate positions in the cylinder and accordingly the valve 10 is caused to 0 en more or less of the ported area in the she l 9, and thereby vary the 'openi for the supply to the steamchest 5. The pressure thus supplied to thesteam chest is admit ad to the turbine through a plurality ofnozzles 40, which connect with the steam-chest through passages 41, formed in the periphery of the head and leading to the supply-bowls 42 for the -nozzles. Governor-controlled valves '43, operatively connected to pistons44, regulate the admission of pressure from the steam-chest to the nozzles. Controlling-fluid pressure flows from a controller-chamber through a passage 45, which communicates by branch passa es 46 with the cylinders for the pistons onnets 47 close the outer ends of the valve-piston cylinders, which may be arand against the piston 18, so that as the ranged around the head in any desired manner.

The means for regulating 'thevalve-cdntrolling pressure may be ofany'desired'char: acter, that shown in Fig. 1 formingthe'subject-matter of a companion application and, as briefly described, com'rises a ,govern'orshifted jet-controller device 48, into which steam flows from the chest throu h a a'ssage 49 ,similar to 41. Thesteamwitil troller device is discharged in a thin-stream, preferably an annular jet, and acts with inector and ejector effect "in a "chamber which communicates, through the passage 50, with the controller-passage 45. The controllerfluid pressure after exerting its impact 'effec't flows off through a nozzle into the turbine.- The adjustment-of the controller 'device' con trols the admission of steam to the nozzles 40. It is my purpose to adjust the device in re sponse to the speed or load conditions ofthe turbine, utilizm the governor 33 for the iin t e 0011- IIO sas es ing to connect the controller device 48 to the rod 29', which'adjusts the valve 27. Thus abell-crank. lever litransmits motion from the rod to a lever 52, pivoted at anintermea; jector or ejectoreiiect of 5 said'and being ope1'ation of the supply-valves.

operating on the main suppl close the supply-ports for the diate oint to a swinging lever 53, Connected to a s ide 54, movable on a lever 55, which is pivoted to the same standard as the lever 53,

The. lever is operatively connected to the stem 56, through which the controller device 48 is adjusted to vary its injector and ejector effect. A shouldered cam-collar 57 is rotated in any suitable-manner and by engagmg lever 52 serves to impart an oscillatory movement through the other levers to the device 48,, the governor determining the point of enga ement between the lever and the collar, an thereby adjusting the jet de vice relatively the pressure in passage 45 by varying the inthe jet. As. the speed lncreases the arm 52 is adjusted, so t at the cam lowers sleeve 54, moves device '48 outwardly, giving greater impact effect to its jet, and causing the increased pressure in passage 45 to close one or more supply-valves, and vice versa, as the speed decreases. As before stated, any other suitable means may be' utilized for imparting motion from the governor to the controller device, as by a direct connection, that above described formlngapart'of my companion application aforedesigned toefi'ect a pulsatory In operation the adjustments between th governor-rod 29, the valve 27, and controller device 48 Wlll be such as to cause a related control. of the steam admitted to and discharged fro mthe steam-chest 5. Thus as the valves 43 are operated by the controller device 48 to introduce any given volume of steam to the turbine the valve 27 will assume a position where the stea'rnjet in chamber 21 ressure against the piston 18,

the demand made u on the steam-chest 5 by the nozzles. As t e nozzle-supply to the turblne increases and decreases the valve 10, will open and steam-chest so as to maintain an admission area calculated to keep the supply to the steamchest equal to the demand made thereon by the nozzles. I prefer that the 'v'alvei10 should always exposea sh htly greater portarea for the admission oi steam to the chest 5 than the combined-area' of the open nozzles. This is parj ticularly desirable when the nozzles are pulsated, as then the steam-chestserves as a r'es ervoir, in which the valve 10 should maintain the mean pressure so that it does not fall be- 65 low the point. calculated to give-the highest to passage'50 and regulating This closing action of the valve thatas t efiiciency'in the nozzles Under nor inalienditions, therefore, the nozzle-valves 43 will control the supplyto the turbine. In case-1 they become stuckor their mechanism is trol'of the turbine independently off-the-nozzle-valves This is a point of great advanta' e, as it does not necessitate the turbine. being shut down for repairs to the actuating mechanism for the nozzlel-valve-con'trrilling'- means, nor will it'be necessary-to sto' the turbine in case of injury to the-valves t emselves until repairs are ready to be m de. I It willbe noted that the valve 10 is unbalanced in its closing direction and is also-acted'upon by'the spring 19, so thatincaseo'f the lowerin of t 'e controller-pressure in the pistoncy inder- 17 the valve will immediately close, thus actingas any ordinarysafet -valv e'-.

W1 be ebtained when the governor under maximum speeds moves the valves 27 to close the port 24 or when in case of breakage ofthe overnor or its connections to the crank 28 t e latter will drop, due to its own weight or that of rod 29-, to a position where the valve 27 closes the passage 22, and thus causes the valve 10 to cut oil the supply.

In Fig. 2 I illustrate a modification of my invention, in which the safety-valve 10 is connected to a stem 58, which passes, entirelythrough the valve casing 59, so that the ,valve substantially balanced. The stem at its left hand end passes througha land or stuffing-bog; andat its end nearest't e overnor is provided with two lon'gitu' inal grooves 61 and 62, divided by a narrow partition 63.- The right-hand end of the -,stex n may alsobe packed,if desired, but-hotlsdas to interfere with the free exhaust through the to the atmos here, while the roove 62 s open to the supp y-pressure in t e valve-casin A reduced extension 64 of the casing in which the grooved portion of, the stem is disposed is provided with adplurality of passages 65, separated at a istance substantially corresponding with the width of the partition 63. Any's'uitable means, such as the'tongue and groove 66 and 67, are "'r'ovided to maintain the grooved portion 0' the stem op osite the passages 65. It follows he stem 58 moves back and forth in the valve-casing it successively exposes the passages to the high pressure or the atmosphere, according to its direction of movement. As shown, these passages connect with fluid-motors 68 for operating the turbine supply valves 69.- The governor 60 is connected to the bell-crank 70 and to one end of the stem 58. The number and arrangement of the passages is such that the governor acts through the relay-power means to succcssi, e y open or close them as the load on the turbine varies, and the valve is so positioned on the stem 58' that it follows the governor and acts in the'manner already described to reduce the ported area through which pressure llows to the turbine.

What .l claim-as new, and desire to protect by Letters Patent, is-

1. In a governing mechanism for a fluidmotor, 'a speed responsive device, valve means controlled thereby for regulating the admission of fluid to said motor, and a safety valve operating on the main fluid-supply and movable IOSPOHSlVO to variations in the speed or load of themotor.

2. In a governing mechanism-for a motor,

' a specd-responsive device, a plurality of valves controlled by said device and regulating the admission of fluid to the motor, a .--:afety-valve means operating on the main supply, and m ans to adjust said safetyvalve means rcsl'ionsive to the varying volume of fluid required by the motor.

3. In a governing mechanism for a motor,

a primary ciintroller means for regulating the controlling nozzle-passages and spccd-responsivemeans to operate said valves Without intermediate positions, which parts constitute a primary controller means, in combination with speed-responsive valve means adapted to operate as a secondary (mntrolle means and act with throttling cfl'ect on the-supply to saidi'iozzle-valvcs only when the latter all mit an excessive supply of fluid to the turblue.

6. in a governing mechanism for an elasticfluid turbine, speed-rcsponsivc means, valve means controlled thereby for regulating the admission of motor fluid to the turbine, and safety-valve moans controlled by said speedrcsponsivc means and adapted to vary the ported area through which motor fluid flows to said admissiomvalve means, in a predetermined relationship to the volume of the fluid admitted bysaid admission-valve means to the turbine.

7. in a turbine, a salety-valve operating on the main flu d-supply and adapted under abnormal conditmns i l vary its volume substantially in accordar, e with the load, a lurality of nozzle-passages through which i uid is discharged against a rotary element in said turbine, valves for cutting said nozzles into and out of service, and a speed-responsive device Which controls said valves independentl of said safety-valve and regulates the fluid supply under normal conditions.

8. A turbine having a stean1-chest, a plurality of nozzles communicating therewith, rotating elements against which said nozzles are adapted to discharge fluid, independent valves for said. nozzles, a speed-responsive device, and a relay-power means controlled thereby for operating said valves, in combination with a valve movable over the sup lyport of said steam-chest and controlle by said speed-responsive device.

9. In comblnation with a fluid-motor having an independent riinary controlling means forregulating the supply of motor- .lluid, a safety-valve operating on the main supply and adapted to assume intermediate positions responsive to the changes 1nthe speed of the motor.

10. In a fluid-motor, a s eed-responsive device, and a safety-valve a apted to operate on the main supply and assume intermediate positions responsive to said device.

11. In an elastic-fluid turbine, a primary controlling-valve for an admission-passage which the motor-fluid tends to open, a-safetyvalve ada ted to cut oil the motor-fluid supply to sai admission-valve, said motor fluid tending to close said safetyvalve, a speedresponsive device which operates said safetyvalve against said motor fluid causing it to assume intermediate positions, and a jdevice for controlling the operation of said admission-valve which is operated by said speei responsive device.

12. I A controlling mechanism for aturbin comprising a plurality of flu1d-adin1ss:-..

valves for the turbine, motors for o crating said valves, a safety-valve in a flui -supply conduit, a motorfor moving said valve with intermediate operating positions to close said conduit, and a speed-responsive device adapted to control said motor separately and adjust said safety-valve so that, in the event of in jury to said fluid-admission valves, said safety valve stands ready in a position to valve off.

excess motor fluid from the turbine.

13. In a governing mechanism for a turbine, a primary controller means which regulates, under the control of a speedresponsive device, the admi. on of motor fluid to the turbine, a safety- .lve adapted to cut oil" the fluid-su 'iply from said. primary controller means, means, under ti .2 control of said speed-responsive device, for operating said safetyvalve with intermediate positions,

or ports for said chamber, and devices to move said latter valve means responsive to speed changes and Without an intermittent cut-off action, as and for the purposes de- 15 scribed. r

15. An elastic-fluid turbine having a pri-' mary controller means which intermittently cuts, off all or part of the supply under the control of a governing means, in combination With a secondary'controller means adapted 20 to operate responsive to speed conditions and to regulate the supply bywiredrawing as contrasted with intermittently cutting off all or part thereof by said primary controller means.

In testimony whereof I have hereunto set 25 my hand in presence of two subscribing witnesses.

JAMES WILKINSON.

Witnesses:

JAMEs H. NOLAN, ACHESON J. CoNDRY

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