US858540A - Governing mechanism for turbines. - Google Patents

Description

No. 858,540. PATENTED JULY 2, 1907. R. H. RICE.

GOVERNING MECHANISM FOR TURBINES. APPLICATION FILED NOV.2, 1906.

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Inventor, Richard H. F2ice,

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N0.'s5s,540. YPATENTED JULY 2, 1907.

R. H. RICE.

GOVERNING'MEGHANISM FOR TURBINE S. APPLICATION FILED NOV.2,1906.

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511858.540. PATE'NTBD JULY 2,1907.

V 11,-11. RICE. GOVERNING MEGHANISM FOR TURBINES.

APPLIOATION FILED 1mm. 190a.

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Ihventor; Richard H. Rice,

No. 858,540. PATENTED JULY 2, 1907;

' R. H. RIGE. GOVERNING MECHANISM FOR TURBINBS.

APPLICATION FILED NOV.2.1906.

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Richar'ciHRice,

No. 858,540 v I PATENTED JULY 2, 1907.

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I GOVERNING MECHANISM FOR TUR'BINES.

APPLICATION FILED NOV-5.1906.

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UNITED STATES [PATENT ()FFICE.

RICHARD H. RICE, F SWAMPSOOTT, MASSACHUSETTS, ASSIGNOR TO GENERAL LEoTEIo COMPANY, A CORPORATION OF NEW YORK. I

. GOVERNING MECHANISM FOR TURBINES.

Specification of Letters Patent.

Patented July 2, 1907. v

To all whom it mag concern:

Be it known that I, RICHARD H. Bron, a citizen of the United States, residing at Swampscott, county of Essex, State. of Massachusetts, have invented certain new and useful Improvements in Governing Mechanism for Turbines, of which the following is a specification.

The present invention has for its object to provide an improved governing mechanism for turbines which i Fig. 2; Fig. 5. is an aitial sectiontaken on line- 55 of Fig. 2; Fig. 6 is a diagrammatic view showing the relation between the speed governor and valve mechanism, and Fig. 7 is a plan view of an embodiment of the invention as'applied to a turbine having a pluralityof regulating valves.

1 represents the casing for the valve actuating mechanism which is bolted or otherwise secured to the turbine casing 2 as shown in Fig. 6. The turbine maybe of any approved type, the one shown being an impact turbine, butthe invention is not limited .thereto.

' Mounted on the main shaftof the tinbine is aspeed responsive device 3, Fig. 6, for causing the opening and closing of the valve or valves as will appear hereinafter. The shaft for actually performing the work of opening and closing the valves is driven by the belt 4 or equivalent means from the turbine or separate source ofzpower. 5 T

Referringnow to Figs. 3 to 6 inclusive, represents the vertically-disposed shaft driven by thebelt- 4, previously referred to, and carrying a worm 6 at its lowerend arranged to mesh .with'the teeth-of the worm wheel 7. This worm wheel is mounted on the secondary horizontal Shaft 8, the latterbeing supported by suitable bearings 12 carried by the casing 1. Mounted on the secondary shaft is a gear wheel 9 meshing with the gear .10 carried by the cam shaft 11. -33 meansof this atrangement the camshaft is constantly rotated while the turbine is in operation,.bu t at a-reduced, speed, owing to-the interposed gearing. The cam shaft is mounted in suitable bearings "12 oarried by the casing and is free to move axially in response-tomovements of the shaft governor. Surrounding the shaft and keyed to it is a cam 13, of suitable shape to ope n and close the regulating valve or valves or other regulating device or devices. .This cam may bemade an integral part: of the shaft or itmay be'madeseparate as shown, if

readily removed and a new one substituted in case of' wear or damage. The gear 10 is also keyed tothe cam shaft and is provided lwith an elongated hub which engages one side of the cam and acts as an abutment therefor. The gearis held against longitudinal movement on the shaft by a spanner or other nut 14. At the opposite end of the cam shaft is a grooved 'collar 15 which is seated against a shoulder on the shaft and is prevented from rotating independently thereof by a key. Between the collar and the cam is a spacing ring 16. It will thus be seen that the parts are so arranged that when the nut 14 is screwed up all of the parts on the shaft will be firmly seated. The cam shaft extending rock shaft 19, Fig. 2, and lever '20. The lever'20 carries a roller 21 at its outer end which is located in thegroovein the collar 15. As the speed governor rocks the shaft 19 to-and-fro, its motion is communicated by the lever 20 to the collar which in turn moves the cam 13 in one direction or the other from the central position shown. With a construction of this kind it "is desirable under certain conditions to provide a means for insuringa certainfdefinite or step-by-step movement in an axialdi-r ection of the valve operating cam, since otherwise the edges of the cam, or those of the members co-operating with the cam, may be injured. As one embodiment-of this feature of the invenv tion, a lever 22, Fig. 2, is provided, which for convenience is made a part of the lever 20 and thus forms a bell crank. On the outer end ofthe lever 22' is a notch 23,

r and interlocking with the notch is a spring pressed projection 24. The notch is preferably formed in a removable piece and said piece may be made adjustable if desired and also the piece carrying the projection.

In order for the inclined walls of the notch 23 to move past the projection 24 in either direction it is necessary for the governor to overcome the tension on the spring 25, the latter acting through the lever 26 on the projection 24. An adjusting screw 27 is provided to adjust the position of the projection 24. By means of this construction all danger of the edges of the cam, or members .co-operating -therewith being injured' is prevented.

With a construction of this kind it is necessary on the one hand. for the speed of the turbine to build'up slightly in order for the governor to overcome the resistance offered by the parts 23, 24, 25 and 26. On theother hand when the speed falls, due to an increase of overcome the opposition interposed by the parts 23 and 24. The resistance interposed by the step-by-step retarding device is not sufficient, however,to prevent the governing mechanism from holding the speed of the turbine constant within the prescribed limits of good regulation. The regulating valve is provided with a stem 28 on the end of which is a cross head 29, and between the crosshead and the end of the valve stem is a coiled compression spring 30, Fig. 4, toprevent injury to the parts in case they are not accurately assembled, and to reduce the shock on the valve due to the opening and closing at the time the cam comes into service.

Mounted on the cross-head and slightly offset, Fig. 2, are two members 31 and 32 comprising rollers, the former'being located on the left handside of the cam shaft and the latter on the right. As shown, the rollers 31 and 32 are both in engagement with the cam 13;

V thismeansthatfor every revolution of the cam shaft,

the valve is opened and closed. When the cam 13 is shifted so that it engages only with the roller 32, the

valve will be closedand remain so until the cam shaft k 25.

is moved either to the position shown or to a point where the cam clears the roller 32 and engages only the roller 31. In the latter case the valve will stay open until there is a change in speed. It is to be noted that all of the parts are submerged to a greater or less extent in oil so,that the wear thereon is reduced to a minimum. r

With. the mechanism just described the admissionof motive fluid to-the turbine may be continuous or substantially so or the valve 33 may be opening and closing every few seconds or it may open and close for every rotation of the cam shaft. This action is dependent upon the load on the turbine relative to the amount of steam admitted when the valve is open and also upon the character of the load; that is whether it is steady or fluctuating.

In the present embodiment of the invention the motive fluid passes'through a nozzle 34, Fig. 6, before striking a row of buckets 35 on the wheel 36 but it may pass through any other form of fluid-discharging vention is not to be construed as being limited thereto unless so stated specifically in the claims.

The invention is shown in connection with an admission valve, but it is also applicable for use in connection' with valves between stages in a multi-stage turbine of any type where it is desired to regulate the passage of fluid at a point beyond the admission. 3

The particular construction of the cross-head, rollers, etc., can be varied without departing from my invention. The cross-head is shown as extending under the cam shaft, although it, may extend over it if desired. Instead of using rollers other. means may be employed to co-operate with the cam to actuate the valve, the. principal feature being to provide a means located on one side of the axis of the shaft 11 co-operatin'g with a cam to close the valve, and a second means located onthe oppositeside of the axis and co-operating with the cam to open the valve. In thepresent embodiment of the invention, the cam directly operates the valve; but if desired, the valve may be op'crated by a suitable motor and the mechanism described be employed to control the motor.

In Fig. 7 is shown an embodiment of the invention wherein a plurality of cams 13 are provided and mounted on the longitudinally movable cam shaft 11. Each cam cooperates with a separate cross-head 37 to open or close a valve, as the case may be. The cams 13 are so set with relation to the rollers that they come into play successively, and therefore open or close the valves one after the other. The retarding device in this figure differs from the one previously described in that the number of notches 23 is increased so that the cams 13 will be definitely brought into-place one after the other. The lever 26 is provided with only one adjustable projection 24 which enters the notches 23 one after the other and causes the cam shaft 11. to be moved axially step-by-step from any given position. With a construction of this character under normal load con ditions, certain of the valves will be open, certain oi them closed, and at least one valve opening and closing more or less frequently to handle that fraction of the load which is greater than that satisfied by a certain number of open valvesi and less than'one more than said number. For example, three valves might not supply the necessary amount of fiuid and four would supply too much, hence the fourth valve would be opening and closing at more or less frequent intervals. The

mechanism is also capable of properly governing the turbine where the load conditions can be satisfied with one valve, as previously described.

The position of the lower cam in Fig. 7 is such that the valve or regulator actuated thereby is in the open position, the next cam above is opening and closing its regulator each rotation of the cam shaft, and the two regulators above are closed because the cams are out of engagement with the rollers on the left hand side of the cam shaft. It is to be noted that the longitudinal movement of the cam shaft is in one direction for successively opening the valves and in the opposite direction for successively closing them. This means, starting from a given position, that a given cam can rotate without engaging either roller; moving the shaft longitudinally from thisposition will cause a cam to engage a roller and close a valve; continued longitudinal movement in the same direction will cause the cam to disengage the closing roller and engage the opening roller, and further longitudinal movement in the same direction will cause it to be disengaged from said opening roller. In other words, shifting a cam to one side of a given position will cause it to move the regulator in one direction; shifting it further in the same direction will move the regulator in the opposite direction, and still further movement in the same direction will cause the cam to be disengaged from the regulator. I may, and preferably do, so. position the parts that a cam is opposite the blosing roller of the first regulator in order that the admission of motive fluid may be entirely cut off from the turbine for a greater or less interval depending onthe load. As the load increases the action of the parts will be as previously described.

In accordance 'with the provisions of the patent statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative, and that the invention can be car-v ried out by other means. a

What? I claim as new and desire to secure by Letters Patent of the United States, is,

1. In a governing mechanism, the combination of a pinrality of regulators, a'rotating actuator for successively further in the same direction to move the regulator in the opposite direction. 7

3. In a governing mechanism, the combination of a regulator, a constantly rotating cam for actuating said regulator, means for transmitting motion from the cam to the regulator, a means for shifting the cam to one side of a given position to move the regulator in one direction and for shifting it further in the .same direction to move the regulator in the opposite direction, .and a speed-responsive device for controlling said shifting means.

4. The combination of a regulator, a constantly rotating cam for ctuating the regulator, means for transmitting motion from the camto the regulator, and a means for shifting the cam to one side of a given position to move the regulator in one direction and for shifting it further in the same direction to'move. the regulator in the opposite direction and for shifting it still furtherin said direction to release the regulator from the cam.

5. In a governing mechanism, the combination of avalve, a constantly rotating cam for actuating the valve;

set portions, a rotating cam located between said portions, and a speed-responsive means for shifting said cam to engage either or neither of said portions to open or close said valve or to permit it to remain open or closed.

7. In a governing mechanism, the combination of a plurality of valves, connections spaced apart for moving said valves, a rotating shaft, a plurality of cams on the shaft so spaced apart that they can engage the connections to open or close but one valve at a;time, means iior shifting the cams.longitudinally t'o actuate the valves; in successive order in either direction, and a speed-responsive de vice to control, the shifting means.

8. In a governing mechanism fora turbine, the combination of a valve arranged to regulate the passage or fluid,

a cam'mounted in suitable bearings for opening and closing the valve, 9. member attached to the valve and located on one'side of and c'o-operating with' the cam for opening the valve. a second member also attached to the valve, and located on' the opposite side of and co-opera'ting with the cam for closing the valve, and a means for causing the cam to operatively engage the said members.

9. In a governing mechanism for turbines, the combiuatlon of a valve to regulate the passage of fluid, a member attached thereto which is active in openingv the valve, :1 second member also attached to the valve which is active in closingthe valve, a means located between the the cams in a step-by-step manner.

members for actuating them, 'anda governor for shifting the means axially into proper co-operative relation with said members as the load conditions change.

10. In a governing mechanism for turbines, the combination of a valve for regulating the passage of fluid, a

constantly running means which opens or closes the valve as the load conditions demand, a governor, and a means which retards the action ofthe governoron said means to insure proper co-operation of the parts.

11. In a governing mechanism for a turbine, the combination of a valve arranged to regulate the passage of fluid,

a cross-head attached to the valve and provided with a member which is active in opening the valve and asecond member which is active in closing the valve, 'a means located between the said members for actuating them, and a device for shifting said means into proper co-operative relation with said members as the load conditions change.

12. In a governing mechanism for turbines, the combi nation of a valve to regulate the passage of fluid, a member attached to the valve for opening it, a second member also attached to the valve for closing it, an actuating means situated between the members and so arranged that when in a mid-position it will open the valve on one part of its movement and will close the valve on another part ,of its stroke, and a governor which shifts the actuating means either side ofsaid position when the load conditions require the valve to be in its open or closed position.

13. In a governing mechanism for turbines, the combination ofa regulating valve, across-head attached thereto, opening and closing members attached to the cross head and offset from each other', a rotating actuator situ ated between said membersja speed governor that shifts the actuator axially and causes it to engage one member' and disengage the other to actuate the valve.

14. In a governing mechanism for turbines, the combination of a regulating valve, a member attached to the valve for opening it, a second member attached tothc nation of a plurality of regulating valves, an opening and a closing member for each valve, a cam for-operating each valve through its members, a shaft upon which the cams are set progressively so that they will engage the actuating members of the valves successively,v and a governor for moving. the shaft and cams axially to cause the latter to open and close the valves in succession.

16.,1In a governing mechanism for turbines, the combi nation of a plurality of regulating valves, an'opening and a closing member for each valve, a cam for operating each valve through its members, a shaft upon which the cams areset progressively so that they will engage the actuating members of the valves successively, a governor for moving the shaft and cams axially to cause the latter to open and "close the valves in succession and a retarding means which causes the governor to move the shaft and 17. In a governlng mechanism for'tnrbines, the combination of a plurality of regulating valves, a constantly "moving actuator for' moving the'v'alves successively, a governor; and a retarding device for the governor which causes it to shift the'actuatoir step-by-step, the said device comprising relatively movable parts, one of which yields after the pressure thereon reaches a certain amount.

In witness whereof, I have hereunto set my hand this thirty first day of October, 1906.

RICHARD H. RICE. Witnesses:

JOHN A. McMsN'us, Jr., HENRY O. Wnsrnnmnr.

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