US954646A

US954646A - Governing mechanism.

Info

Publication number: US954646A
Application number: US39496907A
Authority: US
Inventors: Millard M Pearson
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1907-09-28
Filing date: 1907-09-28
Publication date: 1910-04-12
Anticipated expiration: 1927-04-12

Description

M. M. iBARSON.

P o 9 1 um I. mm mm m Mu at u N m mm VA m L P P A 2 SHEETS-SHEET 1.

In ventoru Millard M. Pea rq on,

Witnesses ARSDTQ.

IGHAN 133M.

GUVEHNING AFPLLSATKON 1 Patented Apr. 12, 1910.

UNITED sTATEs PATENT OFFICE.

MILLABD M. PEARSON, 0F SCHENECTADY. NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

GOVERNING MECHANISM.

Specification of Letters Patent.

Patented Apr. 12, 1910.

Application filed September 28, 1907. Serial No. 394,969.

To all whom it may concern:

Be it known that I, lldILLARD M. PEARSON, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Governing Mechanism for Turbines, of which the following is a specification.

The present invention relates to governing mechanism for turbines, and while more especially directed to those wherein a fluid actuated motoris em loycd to move the valve or valves control ing the admission of motive fluid to the turbine, is not limited thereto.

The invention has for its object to improve the construction of said mechanisms whereby the same parts can be used for a greater number of turbines than at present and especially for turbines of different outputs, particular reference being made to the means for communicating motion from the speed governor to the device COntI'OlllIlg the valve actuating motor.

In one type of machine with which I am especially familiar the shaft is arranged vertically with the turbine at the lower end and an electric generator mounted on top of the turbine, the rotor of which is mounted on the bucket wheel shaft. At the top of the shaft is a speed governor acting on a comparatively long horizontally disposed lover. The valve mechanism is mounted on the turbine casing and the operating motor a convenient point,

therefor is disposed at said casrng.

usually at or about the level of The distance between the end ernor lever and the pilot valve is commonly a number of feet, from two to fourteen not being unusual. These parts are connected by a rod whose length is determined. by the distance between them. As now arranged the. length of the governor lever is changed for practically every different size turbine because of a. difference in diameter of the turbine 0r tl'e generator or both. A change in the lengt of the governor lever results in a change not only of the parts directly connected therewith but also lll changes in the parts constituting the-follow-up device which restores the pilot valve to its initial position after a change has taken' place in sure.

of the go\'-.

the amount of fluid admitted to the turbine. The total number of changes is large and as a result new drawings, patterns, castings, etc, are required, all of which materially increases the cost of production. By my invention I obviate these changes, new drawings, patterns, castings, etc, and so arrange the parts that they can be used on machines differing widely in output and diameter. Usually it will be found best to divide the total number of sizes into groups and to standardize one governing mechanism for each group.

In? carrying out my invention the valve mechanism. the actuating motor, whatever as before or in other suitable positions. The horizontal governor lever may be of any desired length, I prefer to make it shorter than formerly, and is supported and conneefed to the governor in the usual way. Mounted on the generator casing, or other suitable support, is a means or container containing a body of non-compressible fluid whose cubical contents can be changed by the application of external pressure. Mounted on the turbine or other support and connected to the controller of the actuatin motor is a second means or container a so containing a body of non-compressible fluid whose cubical contents can be changed by the application of internal pres- The change in cubical contents of these containers is accompanied by the movement of one or more parts which movement is utilized to perform useful work. Connecting; the two containers is a conduit for conveying fluid from one to the other. When pressure due to the governor is applied extcrnally to one of the containers it reduces its cubical contents, and the fluid discharged therefrom passes through the conduit into the second container and by the internal pressure thus created dilutes, expands or enlarges it in the direction of its lem th. and the movement of some art. thus a I a produced 1s transmitted to the pi ot valve or to the controller of the motor whatever its character. Conversely when the governor acts on the firstcontainer in a manner to increase its cubical, contents fluid flows from the second into it assisted by the elastic nature of the material employed in the construction thereof and by the action of the atmosphere on some art or arts. Other arrangements for assisting this transfer of fluid may be utilized. Connected with the second container and the motor controller is a follow-up device actuated by the same motor.that operates the main admission valve or valves to restore the motor controller to its initial osition.

As a s ecific embodiment of my invention I have s own the containers made out of metal and somewhat similar in construction to bellows. One end of the structure is fastened to a support and the other end is movable. The containers are filled with such an amount of liquid as will cause them to be somewhat diaended at all times. Oil will be found to satisfactory for transmittin motion from one container to the other, ut other fluids may be substituted.

' The structure and type of container can be the widely varied without de artin from my invention as will readily be an erstood by those skilled in the art to which this invention relates. The main thing is to provide an arrangement whereby the governor can act through a fluid column on the motor controller and thus avoid the use of long levers, moving rods, connections, etc., which are in the way and are liable to be injured.

Since the conduit connecting the container can be made of metal and of any length and bent to any desired form, it fol lows that the .same mechanism can be used on machines of widely diflerent output, diameter and shape by merely lengthening the ipe, changing its shape, or both. A condiiit arranged in the manner described will not readil be injured for it can closely follow the out ine of the generator, and will be out of the way. It will not interfere with the position of brackets for supporting allery around the generator, and it avoi s the use of any moving part between the overnor and the motor controller which has eretofore been necessarv.

In the accompanying rawings which illustrate one of the embodiments of my invention, Figure 1 is a partial view of a turbo-generator fitted with my improved turbine governing mechanism; Fig. 2 is a diagrammatic .view illustrating the peration of the motor, controller and foll w-up device; Fig. 3 is a detail view illustrating the driving connection between the motor and the cam-shaft actuated thereby; Fig. 4

is a vertical section of the fluid container actuated by the overnor; and Fig. 5 is a vertical section 0 the fluid container which is connected to and operates the motor conon is a valve chest 2 having an admission conduit. 3. Mounted within the chest are a plurality of valves each operated by a lever 4 and a came, the latter being mounted. on and moving with the oscillating camshaft 6. The shaft is supported in the bearings 7. The camshaft is moved by the hydraulic motor 8 throu h a rack 9 which meshes with a inion 10, *ig. 3, carried by a horizontal sha t 11; the latter may operate only one set of valves or it may extend across the top of the turbine and operate two sets, one on each side. Mounted on the shaft 11 is a beveled gear 12 meshing with a pinion 13 mounted on the cam-shaft'6. T he motor is controlled by a pilot valve 14 shown in dotted lines, F1 1. This valve controls

ports

15 and 16, Fig. 2, leading to op osite ends of the motor cylinder. he va ve normally stands in the position shown and both ports are closed. Fluid under pressure is admitted by the pipe 17 to the space between the heads of the valve and is exhausted by thepipe 18. The valve is actuated by a lever 19 which is connected by pivot20 to the link 21, and by pivot 22 to the moving wall or head 23 of the fluid con tamer-24. The lower end of the link 21 is connected to a bell-crank lever 25; the other end of the lever is connected by the rod 26 to the lever 27 and the lower end of the lever 27 is pivotally connected to the rack 9 or to some part moving with the motor. The lever 19, link 21, bell-crank lever 25, rod 26 and lever 27 form a follow-up device for restoring the pilot valve to the initial position after one or more valves have been opened or closed by the motor, as will ap pear more fully hereinafter.

Mounted on the top of the turbine is a stool 28 which supports-the electric generator 29, the rotor of which is mounted on the shaft 31, which shaft is driven by the bucket-wheels of the turbine. The generator is provided with a suitable cover and mounted on the top thereof is a dome 32 which incloses the centrifugal governor 33 shown in dotted lines. Pivotally mounted on the dome a governor lever 34 which is attached to the governor at the inner end, and at its outer end to an adjustable rod 35. It is also connected to a rod 36 which may be attached to a spring employed for syn chronizing the speeds of two or more ma chines, or for changing the speed at which the turbine will operate, as is well understood. Mounted on a pad formed on the cover is a fluid container 37, the upper wall or head 38 of which is attached to the rod 35. The

containers

24 and 37 may be located wherever desired in line or not and are connecte by the conduit 39 so that fluid may be trans rred from one to the other. outer end of the governor 11 in the present The p instance is intended to have about two inches of movement between the no-load and full-load positions and the head or wall 38 has a corresponding movement. It is desirable, however, to have a eater movement for the head or Wall 23 0 the container 2% and I, therefore, arrange the latter so that it. has such movement. In the present instance the movement is about twice that of the end of the governor lever.

Referring to Fig. 4. 38 indicates the mov able head or wall of the container 37. It is attached air tight to a lan'iiuated metal disk 40 which is in turn fastened to the small ring 41. The ring 41 is also fastened air tight near thc ccntcr to a laminated metal disk 4'2 and the latter is attached at its periphery to the large ring 43. This ring is in turn connected to a laminated metal disk 4-1. The constructimi of the remaining, elements of the container being the same, further description la unnecessary. it should be noted. however. that the lower head or wall is statiouary and is attached to the cover of the generator. Fluid is admitted to the coutaincr through a suitable passage having a plug 45 for closing it and preventing air from entering. \Vhcn in operation the coin taincr is filled with such an amount of fluid as will cause the rings ll and 43 to be sli 'rhtl separated at all times.

3!) indicatcs the conduit for conveying fluid from one container to the other.

The lowcr contuiuf'r differs from the uppcr as shown in Fig. 5 in that the dislts arc made oi one thicknws of corrugated nictal. the arrangement. of the rings 41 and lil l)c ing the same as before. The upper head is secured to a bracket 44 which is attached to a frame piece that guide the stem of the pilot valve. The lowest disk of the series is connected to head 23 and the latter is con ncctcd by part 45 and pivot 22. Fig. l. with thc lcvci' l9. As thc beau 38 of the upper container is moved downward by the govcrnor. fluid is discharged through the conduit 39 into the lower container and forces thc head 23 downward. 'Whcu the outer cud oi" the governor lever 3-1 moves upvardli it ruiscs the licad 3s which tcuds to create a vacuum within the upper container and starts the fiuid into motion. This is assisted by the elastic natur of the disks of the containers and also by the atmosph ric pr ure acting on the nndcr side of the head 22-2. in order to balance the weight. of the lluid column a weight 46 or its equivalcnt'is providcd and suitably arranged as on thc h vcr If llc'lcrring to Fig. 3. and assuming that thc governor has dccrcascd the cubical contents of the uppcr conlaiucr by forcing the hcad 25H downward. this causes the head 23 of the lower containcr to move downward and with 1 it the pilot valve 1 the pivot 20 being the fulcrum. Fluid on hcing admitted by the pilot valve to the right hami end of the cylinder starts the piston toward the left, the exhaust being own, which action swings the lever 27 to the left and moves the rod 26 in the direction of the arrow. This motion is eonnnunicatod to the link 21 and the movement of the latter raises the pivot 20; the pivot. 22 now being the fulcrum. l his ac tion continues until the pilot valve is raised to its initial position where the ports are closed and the motor stops. This action is repeated each time the specd of the turbine is decreased until finally the proper amount of steam admitted to the turbine to satisfy the load. Assuming that. the speed of the turbine in reases. the outer cud of the governor lever ill moves npwardlv and the reverse operation takes place. as will readily be understood; the follou' up device reator' in the pilot val re after the motor piston has: moved a dclinile amountI \i'hen the dianictcr of tin turbine or generator or both is changed it usually becomes necessary to change the location of the m0 tor by moving it toward or away from the shaft. Such a change with constructions heretofore used requires an angular change in the position of the governor lever to com pcnsate lhcrctor because the radial plane of the pilot. valvc is changed. hanging the angular position of the governor rod changes the angular position of the bolt holes in the dome and. generator cover, hence the (lrilling can out he done otter he posi tion of thc olh r part is determined. This requires additional drawing and in tructious and prevents the tat-tor trom making up a large numbcr of ataudard parts. With my im'cutiou thcsu objections are avoided.

l have shown my invention in conncclion with a vcrtical shaft turbine. hot it. is also applicable to horizontal shall tnihincs. and is especially applicahlc wlu-rc thc govcruo is on one cnd of tho ha l't ncar thrgenerator and the valve m chanism and motor at the other.

In accordanc with thc llllft'irlflilR of the patcut statutes. i haw \lcscrilnui the principle of operation of my lli\' ill f-ti together with the apparatus which i now considcr to roprcscnt th bcsl cnibodinit-nji ihrrcof; but i (ll-sire to have it undcrstood that tho apparatus shown is only illu trahivc. and that thc invention can he carri d out in other means.

hat I claim as now and elcsirc to by Letters l'atcnt oi the {hr 4% Stair-r. ia.-

l. The combination of a. ti; sine and its casing. a pccd governor driacn is the turbino shat't, a govcrnor later vaivc mechanism for controihng the admzssio rof motive fluid to said turbine and suitably mounted with respect to the casing, and a fluid transmission means connecting the governor lever with said valve-mechanism.

2. he combinatioi' of a turbine, a valve controlling the admission of fluid to the turbine, a motor for mofing the valve, a controller tor the motor. a speed governor driven by the turbine, and a fluid transmission means for communicating movements of the governor to the controller.

3. The combination of a turbine, a valve controlling the admission of fluid to the tarbine, a fluid actuated motor for moving the valve, :1. controller for the motor, a speed a governor driven by the turbine shaft and located at a point remote from the con- JIUHEI', a fluid transmission means for corn' -mun1catn1g the movements 0.: the governor to said controller, and a follow-up device for restoring the controller to its initial position.

4. The combination of a turbine, a valve mechanism controlling the admission of fluid thereto. a motor for actuating said lllQlhtlIh l ism, a controller for the motor, a speed govcrnor. and fluid containers whose cubical 1 contents are variable, one of which is mccharlie-ally connected to the governor and the other to the controller, the containers, being so arranged that when one has its l cubical contents decreased those of the other increase. l

5. In a. governing mechanism, the coinhi nation of a valve, a motor for actuating it, I a controller for the nmtor, a fluid container f which expands and contract-s under changes 1 in pressure for actuating the controller, and a speed governor for causing the container l to act in response to load changes to move 5 the controller. 7

(3. In combination. a turbine, a valve controlling ihe admission of motive fluid thereto. a motor for actuating the valve, 4: controlling devic for the motor, a fluid container which expand and contracts nutter, hanges in f ltr-nlll't, a governor responsive to changes in H Utt'tl oi the turbine shaft for causing the container to a t. and a serond ctmtaincr acted upon by the fir t tor moving the controlling device.

T. In combination, a. turbine, a valve controlling the admission ot motive fluid thcrcl to, a motor for actuating the valve. a. corn trolling device for the mot r. a iluiil con 5 taintwhich ll i1lll' anti ontracts untlcr chang s in t a. governor reslaliniw t to small .ihonor for cousin Illl' Ull I l *C tlll llli ll jnlzlli il [H'tlli ifthr i l t through a tlunl rolown for mo ontrolling (,ltVltlf, and 1 it 'iollon up z w wi'onnwttil to in" control devise and to a pa moving with the motor lo] 'tflli'lJH" intcontrolling devi e,

to its normal ainotioi'z. l

actuating the valve,

c nta incii log, a valve nnahanism for 8. In combination, a turbine, a valve controlling the admission of motive fluid thereto, a motor for actuating the valve, a con trolling device for the motor, a fluid container which expands and contracts with changes in external pressure applied thereto, a second fluid container remote from the first which expands and contracts with changes in internal fluid pressure and actuates the controlling device, and a governor responsive to changes in speed of the turbine shaft which varies the pressure on the first mentioned container.

9. In combination, a turbine, valve mechanism controlling the admission of motive fluid thereto, a motor for actuating said mechanism, a controlling device for the motor, a fluid container Whose capacity can be varied, a second fluid container remote from the first WllUSG capacity can also be varied and which acts on the controlling device, a conduit connecting the containers so that a change in capacity of one results in a change in capacity of the other, and a governor driven by the, turbine shaft which acts on one of the containers in a manner to vary its capacity as the load changes.

10. In combination, a turbine, a valve for admitting motive fluid thereto, a motor for a controlling device for the motor, a fluid container one part of which is capable of movement in the direction of the lcn 'th of the container a second fluid container one part of which is also capable of inovcn'ient in the direction of the length of the container, the amount of movement of one of said parts being greater than that of the other, a conduit conveying fluid from one container to the other, a connection between one of said parts and the controlling device, and a governor tions in the length of a fluid container as the load changes.

1]. The combination of a. turbine, a valve mechanism controlling the admission of motive fluid to the turlnne, :1 motor for actu ating the valve mechanism, a controlling dcvirc for the inotor, a container having an elastic wall and containing liquid, a second rmmnunicating with and situated at a point remote from the first, one wall 01' which is al.-o elastic and is connected to the controlling device, and a governor responsive to load changes which acts on one of said containers in a manner to increase or decrease izs cubical contents.

12. in combination. a turbine. and its cas controlling the admission of motive fluid thereto and supported by the tnrhinc casing near its peripher v, a. controller for th motor, a speed governor mounted on the turbine shaft and mechanism, a lever actuated by the govfor causing varia-.

ernor, and a fluid transmission means for communicatin the movements of the lever to the control er.

13. In a governing mechanism, the combi- 5 nation of a valve, a motor for actuating it, a controller for the motor, a governor, means acting through a body of flmd for transmitting the motlon of the governor to the controller, and a means for counterbalancing the weight of the fluid. 10 In witness whereof, I have hereunto set my hand this 27th day of September, 1907. MILLARD M. PEARSON. W'itnesses:

BENJAMIN B. HULL, HELEN ORFORD.