US1559782A

US1559782A - Governor

Info

Publication number: US1559782A
Application number: US538390A
Authority: US
Inventors: Frank H Rogers
Original assignee: William Cramp & Sons Ship And
Current assignee: William Cramp & Sons Ship And; William Cramp & Sons Ship And Engine Building Co
Priority date: 1922-02-21
Filing date: 1922-02-21
Publication date: 1925-11-03
Anticipated expiration: 1942-11-03

Description

4 Nov. 3, 1925.

F. H. ROGERS GOVERNOR Filed Feb. 2-1, 1922' 2 shuts-shut 2 75 (lose Pawnee Not. 3, 1925.

, UNITED, STATES,

FRANK H. access, or PHILADELPHIA,

P TE NT oFricE.

PENNSYLVANIA, assrcrro'n. 'ro wm-Lmn cam & sons srnr AND ENGINE BUILDING- comranzn oo'ncrom'rrou or rmnr- SYLVAINIA.

cov irmoa.

Application filed February 21,1922.- Serial'No; 538,390.

specification.

This invention relates to governors and particularly to a governor for regulating the speed of a hydraulic turbine; The chief object of the invention is to provide a governor which will regulate the flow according to the load in the mostefiicient manner and without causing overregulation or hunting and danger of water hammer due to sudden variations in the flow. 'A further a which object of the invention is to combine an automatic regulation and hand regulation together so that the shift from one to the other, may be easily made at any instant without special preliminary adjustment of either-regulation and without changing the position of the'turbine gates or danger of losing control of the unit.

A further ob 'ect of the invention is to' provide a governor in which the various mechanisms will be gathered together and combined within a" unitary structure supported from a single stand.

Further objects of the invention particularly in combining ruggedness and strength with simplicity of structure and in reducing to ,a minimum the number of adjustments to be made by the operator so as. to simplify his duties intheplantwill appear from the following description taken inconnection with the accompanying drawings, in

Fig. 1 is a sectionalside elevation through agovernor stand Fig. 2 is an end elevation of the same with parts shownin section. v

Fig. '3 is adiag'rammatic layout of the combined governor and hand control, and

1 Figs. 4 and 5 are sectional views of a special clutch device.

The governor consists! primarily of a vertical shaft 1,= the: lowbr end of which isdriven from the main turbine shaft either throughbelt and. ulleys or bygeared con- -'nection.- This sha ernor base plate 31, and

rotates in a roller bearing 2 which actsas a combinedfsteady and thrust bearing. This bearing is supported in a sleeve 3, which in turn is secured to the upper part of the governor stand 4 supported on the base 31. The top of the shaft is directly connected'to the governor head 5, which carries the two'fiy weights 6,'so that these weights revolvewith the shaft. The centrifugal force due to motion is resisted by the springs 7, which'are held in '9 and links 10, to the collar 11, so that the place between the weights: and the rods 8. The weights 6 are connected through leversmovements of the weights 6 in a horizontal I plane produce corresponding movements of the collar 11 in a vertical plane. Allof these parts however rotate with the shaft 1. The vertical movements of-collar 11 are transmitted. to the long floating lever 12,

by means of a shoe connected to lever 12 near its center, and running in a groove'in collar 11. One end of1ever12is mounted .to the pilot valve stem 13,'and the opposite end of lever 12 is connected at '14 to the short floating lever 15., The long floating lever 12 consists of two arms connected by cross bolts 16, so that the short floating Qlever lfi'which; consistsof but a single arm,

,may bewlocated 'inside of the long lever.

One end of the short lever 15, is connected through a link 17, to the piston rod 18 of the dash pot 19. The other endof the short lever 15, is connected through a link 20, to the cross head 21, which inturn is' connected through a' screw to thee ring rod 22. This rod 22 runs through t e spring 23-which is contained within the casing 24. The washers 25 above and below the spring ;23,-permits vertical motionsofcthe rod 22 by compressingthe spring 23. The 'central' portion-of the short lever 15 connected through link26 -to'the restoring rod 27, which is in turn connected at the adjustable point 28', to the restoring lever- 29. Lever 29 rotates-on shaft 30 supported inthe gov as a connection at -32 to the restoring .'sha ft 'not shown whichis connected [to the operating cylinder shaft:

which controlsgthe turbine gates..

The; pilot 5mmrod 13 -is' connected.

I through} ball? and socket }jointf-33 topthe pilotv valve: 34. ,This pilot-valve operates inside of :the main governor valve 35 1n such 10s: away that themam governorqvalve 35ex- I actly followsevery motion of the pilot valve 34. This is accomplished in the following manner.

Fluid under pressure is admitted through a pipe 136 to a central chamber 36, which is connected through drilled holes to the inner chamber 37 A movement of the pilot valve 34 in an upward direction admits pressure through the drilled hole 38, to the bot-. tom of the main valve 35, thus causing this valve to rise until the pressure supply from 37 is cut oil. In order to permit the vertical inotion of the main valve v35, the pressure above this valve is relieved through the drilled hole 39, permitting the fluid to flow into chamber 40, and thence to chamber 41, and out through the exhaust pipe 140. Similar action occurs when the p1lot valve 34 is lowered, resulting in a similar move ment in a downward direction of the main valve 35.

The arrangement of the parts of the said valve 35 causes the fluid under pressure from chamber 36 to flow into' chamber 42 for upward movements, so that this fluid will flow through chamber 43 to the pipe 44, which is connected to the closing side of the main operating cylinders connected to the turbine gates. At the same time, the upward movement of the main valve '35 connects chamber 45 with exhaust chamber 41. As chamber 45 is connected to pipe 56 shown in Fig. 3, such a movement of the main governor valve permits the fluid to exhaust from the opening side of the operating cylinder 69, and thus permits this cylinder to move in the proper direction to close the turbine. gates. When the turbine unit is operating under normal conditions at a steady load and normal speed,..the position of the fly weights 6, is such that the pilot valve 34 is held in its central position, resulting in the main valve 35 being held in central position and hence cutting oil all gow of the fluid from the operating cyliners. In case of a reduction in load on the turbine, the speed of the unit will start to in crease, resulting in an outward movement of the governor weights 6 and a corresponding vertical rise of the pilot valve 34 and the main valve 35. This movement, as explained will admit pressure from the governor system to the closing side of the main operating cylinder controlling the turbine gates. As the turbine gates close, the restoring connection from these gates attached to the lever 29, will cause an upward movement of the restoringrod 27 This will result in an 'upward' movement of the lever 15. Due to the resistance to motion of the dash ot 19, this end of the short lever 15 will almost stationary, resulting in an upward movement of the other end of the short lever by compressing spring 23, and

consequently an upward movement of the 3 end of the long lever 12. As the long lever will pivot about its point of connection to collar 11, the upward movement of one end will result in'a downward movement of the other end and this movement will consequently tend to restore the pilot valve 34 to its original position and thus stop the movement of the turbine gates. However, due to the fact that the turbine is producing more power than is being demanded by the generator, the speed continues to increase and the turbine gates continue to close, until the point is reached where-there is a balance between load demand and power supplied. At this point the turbine gates will stop moving, due to the restoring efiFect on the pilot valve 34.

The action so far described is thefirst phase and is known as the primary restoration. It will be appreciated that at the end of this primary restoration, the turbine to its, original position and thus exerts a force on the piston in the dash pot which will slowly move to its new position, the rate of motion depending on the setting of the bypass valve 145. The downward movement of the rod 22 results in a corresponding downward movement of the end 14 of the long lever 12 which causes an upward movement of the other end of lever 12 and a corresponding upward movement of pilot valve 34 and the main valve 35. This slight additional movement 'of the main valve 35 results in a further closing movement of the turbine gates and thus brings the speed of the unit back to normal. This secondary restoration is however a slow movement in order to bring the speed back to normal without the danger of oscillating below and above normal.

It will be noted that the connection 46 between the link 20 and the short lever 15, is adjustable by' means of the thumb screw 47 and-if this adjustment is such that connection 46 lies directly in linewith connection 14, the governor will so operate as to give constant speed of the turbine irrespective of the load on the machine' This is due to the fact that after both the primary and secondary restoration have taken full effect,

connections

46 and 14 have returned to exactly the same position and the other end of lever 12 which is attached to the pilot valve has also returned to its original position, and hence the center of, lever 12 which is connected to the collar 11, must be in its original position which can only correspond properly divide load changes. This change in speed is termed inherent speeddropand the. governor is adjusted so that the speed of the. unit will decrease from 1% to 3% as the load is increased from zero to full load.- This is accomplished by so adjust-- ing the thumb screw 47 that

connections

14 and 46 will be slightly apart as shown in Fig. 1. 'With such an adjustment the elevation of connection 14 will vary slightly for eachposition of the turbine gates, for it is evident that as the turbine gates close, restoring rod 27 rises, connection 46 always returns to the same position and hence connection 14 will also rise resulting in slightly higher speeds of the turbine as the gates close.

It is usually desirable in power plants to maintain constant speed of the units at all loads, and therefore a means is provided by which the operator can adjust the speed to normal after load changes have occurred in the plant. This adjustment is taken care of by means of the hand wheel 48. This hand wheel is attached tosleeve 24 which in turn is attached to bushing 49, which bushing is keyed to rod 22. Therefore, by revolving the hand wheel 48, the cross head 21 can be raised or lowered in order to ad just the-speed to normal for each load on the unit. This adjustment can also be made 7 by means of .the small motor 50, which is usually controlled from the switchboard gallery so that the speed of the unit may be adjusted by means of it from the switchboard gallery.

The .revolving element of the govenor is protected by a stationaryhead 51 which is secured to the overnor stand 4. Above the stationary hea is mounted a sight feed oil cup 52 which provides lubrication through pipe 53 r to the governor collar 11 and also to the thrust and steady bearing 2 The oil after passingthrough these hearings collects in chamber 54 and is thence drained oil through cook 55.

This governor is also provided with a gate limiting device which may be set for any predetermined maximum gate opening desirable on the unit. This gate limiting device consists of a rod 94 (Fig. 1) connected to a boss on restoring lever 29, so that this rod 94 moves in synchronism with the turbine gates. To this rod is attached a screw section 95 which drives a lever 96. As

the turbine gates open, lever 96 is revolved in a clockwise direct-ion until the face 97 of the lever com'es in contact with rod 93 which rod' is directly connected to the main governor valve 35. Therefore, for a given set readily be set. This gate limiting device therefor operates directly on the main gov ernor valve 35 and has no efl'ect whatsoever on the pilot valve 34, the lever 12 or the flyweights 6. In former designs of governors it has been necessary to provide springs in connection with the pilot valve rod in order to permit further movement of the flyeights after the gate limiting device has prevented further movement of the pilot valve rod. In the present design of gov ernor it is noted that the gate limiting device acts directly -on the main governor valve 35 and therefore free movement of the pilot valve 34 and its connections to the flyweights is v permitted Without. danger of opening the turbine gates a further amount. In connection with the above mechanism providing for the automatic regulation of the gate opening according to the load it is also often desirable to provide hand control of the gate mechanism to take care of the starting up of theunit and periods during which the automatic mechanism'is disclearly in diagrammatic form in Fig. 3

'ting of lever 96, when the gates have arwhich also shows in outline the automatic. I

mechanism and its connection to the turreturn tanks are also shown diagrammatically in Fig. 3. The fluid under pressure enters through pipe 57 and passes to the center chamber 36 (Fig. 1) of the main governor valve. Pipe 44 connects chamber 42 of the main governor valve to the closing side of the operating cylinder 69. "Pipe 56 connects chamber 45 of the main governor valve to. the opening sideof the operating cylinder 69. Pipe .58 connects the exhaust chambers 41 of the ma-in governor valve to the sump orreturn tank from which the governor pumps draw their supply. In

order to shutoff the ove'rnor,pressure operated plunger valves 2 are provided in the governor valve casing 73. It is usual to provide three of these plunger valves for shutting ofi flow through

pipes

44, 56 and 57, as it is usually not considered necessary to pro valves and pressure is exhausted from the annular chamber 75- of all three valves.

This causes the plunger .valves to close against the seat rings 7 6 and thus prevents flow of the fluid between the main governor valve 73 and the operating cylinder 69. These three valves 72-are operated by means of the lever 77 and the four way plug cook 65. By referring to Fig. 3, if the lever 77 is moved to the position indicated in full lines for hand control operation, the plug cock 65 is'so rotated as to introduce fluid pressure on the top of the plunger valves 72 from pipe 57 through the

pipes

59, 63 and 62. At the same time, such setting of the plug cock 65 relieves the pressure from the annular chamber 75 of the plunger valves through pipes 61, 60, 64 to 58. With such a setting therefore of the'plug cock, all of the plunger valves 72 move simultaneously to the closed position and so shut off the main governor operation. hen lever 77 is moved to dotted line position 78 for governor operation, conditions are reversed so that the plunger valves 72 are all moved by fluid pressure to their open position and the governor is in operation. I

The hand control valve is located in pedestal 79 Fig. 2. The valve proper 80, controls the flow of the pressure fluid to the operating cylinder 69. The hand control valve 80.as shown in Fig. 2 and diagramin Fig. 3 is in its central position maticall he valve covers the ports in the valve so that t chamber 81 and thus prevents any flow.

When lever 77 (Fig. 3) is set on the hand control position the pressure from pipe 57- is connected by pipe 59, plug cook 65, and

pipe 63, to the central chamber 82 of the hand control valve. The hand control valve 80 is operated b means of the hand wheel 181. This han wheel rotates shaft 182 which is provided with a threaded. portion 183 (Fig. 4) so that when the hand control is in operation, the clutch; 184 is raised or lowered by means of hand wheel 181.

Clutch 184 is connected to one end of lever 85 (see Fig. 2) which is pivoted at point 86 and connected at its other end with rod 87 i i which directly controls ,the hand contro 'valve 80. In Fig.v 3 which shows the arrangement diagrammatically, clutch 184 is shown directly connected to shaft 187. When the unit is on hand control, the lever 77 is in suchaposition that clutch 184' is thrownin. In this position the clutch jaws 185 (Fig. 3) which are attached to clutch 184 are in mesh with screw thread 183. r Fig. 4 shows the clutch thrown out of gear When the unit is being operated on hand control, a movement of the hand wheel 181 to raise the valve 80 results in pressure being admitted from central chamber 82 through pipe 88 and pipe 44 to'the closing side of the operating cylinder 69, and at the same time permits the exhaust of the fluid from the opposite side of operating cylinder 69 through

pipes

56 and 89, to chamber 90, and thence through pipe 60, plug cook 65, pipe 64,.and pipe'58 to the sump tank. When the hand wheel 181 is turned in the opposite directionthe valve 80 is lowered and the flows are reversed so that the operating cylinderopens the turbine gates.

In order to properly control the unit gates is in exact proportidni to the movement of the hand wheel 181. This restoring mechanism is shown in Fig. 3 diagrammatically, and shows the connection between the operating cylinder rod 70, through lever 91 to rod 182. In the actual construction of the governor as shown in Figs. 1 and 2, the restoring connection from the operating cylinder rod 70 is made to the lever 29 which is mounted on the operating shaft 30. This shaft is connected togrod 182 by lever 92 so that as the turbine gates move, the restoring mechanism will return the valve 80-to its central position through the movement of rod 182, clutch 184, lever 85 and rod 87.

When the hand control lever 77 is moved to the position of governor control 78, the hand control valve is. cut out by means of the plug cook 65 and the pressure inpipe 60 is prevented from operatingv on the hand control valve 81 by means of the check valve 67. When lever 78 is in position for governing operation, clutch 184 is thrown out so that the jaws .185 are no longer in the unit is operating on governor controh. vthe hand control valve 80 is always held 1n its central position .and is not affected by any movement ofthe turbine gates, due togoverning action.

At any time when-1t is desirable to change the unit from governor to hand control,this

-may be accomgilished by merely throwing over lever 77 rom position 78 to full line position, which simultaneously accomplishes the three requirements namely: Shutting off the governor entirely by closing. the three plunger valves .72, admitting pressure to the hand control valve 81, and throwing clutch 184 into mesh. This operation is accomplished in a fraction of a second and without any danger of moving the turbine gates from.their position before the change was made. In other types of governors this result cannot be accomplished for the 'hand control is separate and it is always necessary to set the hand control valve at the particular gate opening at which theunit is gle base. The main governor pedestal is at the center with the valve mechanism and hand control on surrounding pedestals standing on the same base. The shift lever 77 and hand wheel 181 are conveniently located together and all the operating parts are easily accessible for inspection and repair. With this simplicity of operation is combined rug gedness of structure and delicacy and ac-' curacy of operation.- Though the automatic and hand controls are instantaneously interchangeable by the throwing of a single lever yet each when in operation is entirely independent of the other. The automatic control is left wholly free to float to positions as determined by the turbine speed and the positions taken by the regulating gates.

I claim: 1. In a governor mechanism for hydraulic turbines the combination with a supporting base separate from the turbine andspaced therefrom, of a governor pedestal on said base comprising a governor head, and additional pedestals for hand control mechanism and auxiliary equipment separately supported on said base.

2. In regulatin mechanism for hydraulic turbines the com ination with power operated means for controlling the flow, automatic governing means and hand controlmeans for controlling thesupply of power to said power operated means, restoring mechanism for said automatic. governing means and hand control means, and means for correlating the movements of said auto- In regulatin mechanism for hydraulic i turbines the com ination with power operated means for controllingthe flow, automatic governing means and hand control means for controlling the supply of power to said power operated means, restoring mechanism fors'a1d automatic govermng means and hand control means, and means for. correlatingthe movementsof said automatic and hand-control means so that they are instantaneously interchangeable without preliminary adjustment oteither.

&. In regulating mechanism for turbines the combination with power operated means for controlling the flow, automatic governing means and hand control means for controlling, the supply of power to said power operated means, restoring mechanism for saidautomatic governing means and hand control means, and means hydraulic I for-correlating the movements of said automatic and'hand control means so that they are-interchangeable by a movement of a single member without of either.

5. In a governing mechanism for a hypreliminary adjustment draulic turbine, the combination with automatic governing means comprising governor valve mechanism, of hand control means. comprising hand operated valve mechanism and restorlng mechanism therefor, and shift means -for closing or opening the governor valve mechanism and simultaneously connecting and disconnecting said hand oper ated valve mechanism. i

6. In a governor mechanism for a hydraulic turbine, the combination with gate operating means, of automatic governing means comprising governor valve mechanism, hand control means comprising hand operated valve mechanism and restoring mechanlsm therefor, and shift means for closing or opening the governor valve mechanism and simultaneously connecting or disconnecting said hand operated valve mechanism with or from said gate operating means.

7. In a governor mechanism for a hy. draulic turbine, the combination with ate operating means and restoring mechanism, of automatic governing means comprising governor valve mechanism, hand control means comprising hand operated valve mechanism, and shift means for closing or opening the governor valve mechanism and simultaneously connecting and disconnecting said hand operated valve mechanism with or from said gate operating means and restoring mechanism.

8'. In a governor mechanism for hydraulic turbines, the combination with a/hand control valve and gate mechanism of means for operating said valve comprising a hand wheel, and means for restoring said valve to central position by movement of said gatetion to stop the movement of the turbine gates until further movement of said hand wheel.

10. A governor mechanism for hydraulic turbines having a hand control valve and automatic control equipment mounted in twin vertical pedestals supported on a base plate which also supports the governor stand.

11. In a governor for hydraulic turbines the combination of a long floating lever and a short floating lever, of a dash pot connected to one end of the short floating lever and having an adjustable .by-pass attached to the piston of the dash'potso as to vary the time of stroke of this dashpot and thus the secondary compensation to act in the most-eficient manner.

12. In a. governor for hydraulic turbines the combination of a long floating lever and a short floating lever, of a restoring rod connecting an intermediate point of the short floating lever to a lever located within .the governor base and linked to the piston of the main operating cylinder of the turbine-gates.

13. In a governor for hydraulic turbines a gate limiting device in which an element mechanically moved by the turbine gates is brought in contact with an element moved by fluid ressure.

14. In a governor for hydraulic turbines a gate limiting device acting on the main governor valve so that when the turbine gates arrive at a predetermined maximum opening, further opening movements of the gates are prevented by mechanically preventing any further opening movement of the main governor valve.

15. In a governor for gate limiting device consisting of levers and links, located in the governor base plate, and driven from the restoring mechanism-connected directly to the turbine gates, these levers and links being so arranged that "for a given setting, one of the levers 'will come in direct contact with a projection on the bottom of .the main governor valve and thus prevent further opening movements of this having restoring mechanism and means for ermit f hydraulic turbines shifting from one tothe other of said governing means.

17. In a governor mechanism for a turbine a plurality of governing means each having a restoring mechanism and means for shifting. from one to the other of said governing means, said last means comprising restoring mechanism connecting and disconnecting means.

18. In a turbine governing mechanism, a restoring mechanism, comprising restoring and restored elements and a clutch connected to one of said elements and adapted to release the other ofsaid elements for independent movement and to grip said other element so as to connect and disconnect said elements at any desired point in the operation.

19. In a turbine governing mechanism operating means, a pair of governing means acting alternatively to control the supply of power tosaid operating Imeans and comprisingrestoring,mechanism, and means for shifting from one to the other of said governing means, said last means comprising a device forrendering said restoring mechanism inoperative. v

20. In a regulating system for hydraulic turbines automatic regulating means and remote operated means constructed and arranged to regulate saidturbine to the exclusion ofsaid automatic means, each of said means comprising. restorin mechanism.

21. In a governing mec anism for turbines automatic governing means controlling the supply of power to the turbine gate operating means and hand control governing means controlling the supply of power to I the turbine gate operating mechanism comprising restoring mechanism, and means for shifting from one to the other of said governing means.

22. In a governing mechanism for turv bines automatic governin means controlling the supply of power to t e turbine gate operating means and remote hand control gov-v erning means controlling the supply o9 power to the turbine gate operating means and comprising restoring mechanism, and means for shifting from one to the other of said governing means. I I

23. The combination of a turbine governing means, a member movable from an initial position to control said means, a conmotion between said means and member for returning said member to itsinitial position, other means for controlling said turbine governing means and a device arranged to break said connection andrender said other; eans available to control said governing means.

24. In a regulating system for hydraulic turbines a controlling valve comprising cooperating parts both of which are movable, a controllingmeans for one of said parts,

and means for limiting the movement of the other of said parts.

25. In a regulating system for hydraulic turbines a controlling device comprising cooperating contacting parts both of which are movable to control said turbine, fly weights connected to one of said parts for'moving the same and separate means for limiting the movement of the other of said parts.

In a regulating system for hydraulic turbines a controlling valve comprising cooperating parts both of which are movable to control said turbine, fly weights connected to one of said parts for moving the same and gate limiting means for controlling the movement of the other of said parts.

27. In a turbine gate operating mechanism, controlling means thereforand an adjustable means movable with said gate operating mechanism for limiting the operation of said controlling means so as to limitthe extent of movement of the gates.

28. In a turbine, gate operating mechanism, controlling means therefor comprisingfly weights, a valve member movable thereby and a controlling 'piston movable in response to the movement of said valve member and a gate limiting device comprising a movable stop for said piston.

29. In a governing mechanism for turbines, fly weights and a controlling valve member moved thereby, operative connections between said member and the turbine mounted upon saidgates and other means cooperating with 30. In a controlling means for hydraulic turbines a base, a plurality of pedestals mounted upon said base, controlling devices carried b said pedestals and o erative-connections i or said devices exten ingthrough said pedestals and base.

31. In a controlling means for hydraulicturbines a base, a plurality of pedestals mounted'upon said base, controlling devices carried by said pedestals and operative connections between said devices extending through said pedestals and. base.

32. In a controlling means for hydraulic turbines a base, a 'lurality of pedestals ase controlling valves carried by said pedestals and fluid andme: chanical operative connections between said devices extending through said pedestals and base. a 3.3. In a turbine gate operating mechanism, a valve for controlling said mechanism, a pilot valve for controlling the op eration of said first named valve, said ilot valve com-prising cooperating parts bot of which are movable, speed responsive mechanism for controlling one of said parts and gate limiting means for limiting the movement of the other of said parts. A

- FRANK H. ROGERS.