US766667A

US766667A - Governing mechanism for turbines.

Info

Publication number: US766667A
Application number: US17531503A
Authority: US
Inventors: Edward Cheshire
Original assignee: Individual
Current assignee: Individual
Priority date: 1903-10-01
Filing date: 1903-10-01
Publication date: 1904-08-02
Anticipated expiration: 1921-08-02

Description

N0. 766,667. PATENTED AUG. 2 1904. E. CHESHIRE.

GOVERNING MECHANISM FOR TURBINES. Arrmonzox rmzn 00w. 1, 1903.

H0 MODEL. 3 BEEETE-BHBET 1.

f I O I fl I 5 12 6?. 1 n [O ll L O 2 0 o B O O O O I O V O miildlffii v No. 766,667. PATENTED AUG. 2, 1904. E. CHESHIRE.

GOVERNING MECHANISM FOR TURBINES.

APPLICATION FILED OOT.1. 1903.

NO MODEL. 3 SHEETS-SHEET 2.

I /e 6 0" E T'Vl'f 11 e on 6 J.

No. 766,667. PATENTED AUG. 2, 1904.

E. CHESHIRE.

GOVERNING MECHANISM FORTURBINES.

APPLICATION FILED 0OT.1,1903.

N0 MODEL. a SHBETSSHEET a.

Patented August 2, 1904.

EDIVARD CHESHIRE, OF MIIAVAUKEE, ISCONSIN.

GOVERNING MECHANISM FOR TURBINES.

SPECIFICATION forming part of Letters Patent No. 766,667, dated August 2, 1904.

Application filed October 1, 1903. Serial No. 175,315. (No model.)

To all whom it may concern.-

Be it known that LEDWARD CHESHIRE, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented a certain new and useful Improvement in Governing Mechanism for Turbines, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

It is essential for the successful and economical operation of turbines that they be driven at the speed for which they are designed no matter what may be the variation in the load. It has been proposed to accomplish this result by means of a governor which shall throttle the supply of pressure fluid to the turbine when the load is lightened and the speed of the turbine becomes excessive. This, however, is subject to the objection that the passages through the turbine are designed to complete the expansion of a definite volume of pressure fluid at a predetermined definite pressure. If then the pressure fluid be throttled, a small volume thereof is admitted, which completely expanding reduces the pressure below that for which the turbine was designed. In the case of the employment of steam as the pressure fluid condensation occurs in the turbine, causing great losses by fluid friction.

The object of my invention is to so govern the admission of pressure fluid to the turbine that whenever the latter is receiving such pressure fluid the volume and the pressure of such fluid shall be constant.

Another object of the invention is to provide the controlling-valve for the pressure fluid admitted to the turbine with means independent of such fluid for operating the same. This actuating means may be compressed air, steam, or electricity.

In the embodiment of my invention herein disclosed I employ a hydraulic motor, and as an economical means for operating the same I employ therewith the oil supplied to the turbine-bearings by a forced-feed lubricator driven by said turbine, operating such controlling-valve whenever the speed of the turbine exceeds or falls below the predetermined limits at which it is desired to operate the same.

The invention may be defined generally as consisting of the combinations of elements set forth in the appended claims, by which the above results are accomplished.

Referring to the drawings, Figure l represents a side elevation of the turbine; Fig. 2, an elevation of such turbine viewed from a position at right angles with respect to Fig. 1, portions of the governing apparatus and turbine being shown in section; Fig. 3, a vertical sectional view of thehydraulic motor and its valve mechanism; Fig. 4, a similar view of the hydraulic-motor valve mechanism and its operating means; Fig. 5, a plan view of the apparatus shown in Figs. 3 and 4.

A represents a turbine of the parallel and radial flow type provided with a supply-pipe B B fo admitting steam or other pressure fluid to the inner portion thereof. This turbine forms the subject-matter of application Serial No. 177,368, filed October 17, 1903, and constitutes in its details no part of the invention embodied by this application.

The pressure fluid, hereinafter referred to as steam, is admitted to the central portion of the turbine through the supply-pipeB B, there being an ordinary throttle-valve b located externally of the casing. As will be apparent from an inspection of Fig. 2, the steam is first admitted to a reeeiving-chamber 0 from which it flows through a valve-eontrolled orifice b to the chamber at the central or inner portion of the turbine. The flow of the steam from the receiving-chamloer to the inner chamber is controlled by the valve 0 which is provided with a long stem 0", extending through the casing of the turbine and provided at its outer extremity with a piston 0 The valve, as shown, is equipped with guidewings 1/ The governing apparatus consists generally of three valve mechanismsnamely, the governing-valve c and its piston 0 hereinbefore referred to; a valve, hereinafter referred to as the hydraulic valve, having a piston attached thereto and adapted by its movements to control the flow of hydraulic-pressure fluid to the piston of the governing-valve, and a valve, hereinafter referred to as the steam-valve, adapted by its movements to 0 containing the hydraulic valve.

.control the flow of steam to the piston of the hydraulic valve to operate the same.

Owing to the pressure of the steam on top of the valve 0 I do not employ the turbinesteam to operate the piston 0 attached to said valve, but depend upon the pressure of some other fluidas, for, instance, oil pumped by the turbineto supply asystem of forced-feed lubrication therefor. This system is indicated in Fig. 1, wherein G represents apump operated by the turbine-shaft D for pumping oil through the ducts 0 to the bearings of such shaft. With this pump are connected pressure and return pipes 0 0 leading to the valve-chest 0 connected with the cylinder 0*, containing the piston of the governing-valve. The end of the pump-shaft is provided with a pulley f, whose movement is transmitted to the pulley f by means of a belt f (shown in dotted lines in Fig. 2,) there being a belttightening pulley or roller f provided near said pump-shaft. The pulley-shaftf is provided with an inertia or centrifugal operating device f which may be of any approved type adapted to operate the steam-valve E.

Carried by the cylinder 0* is the valve-chest This valve-chest is provided with a bushing 0, having ports 0 0 0 therein, the port 0 communicating with the pipe 0 and the interior of the bushing, the port 0 connecting the-interior of the bushing with the passage 0, ex-

tending to the lower end of the cylinder 0*, and the port 0 connecting the interior of the bushing with the port 0 extending to the upper end of the cylinder 0. Vithin the bushing are the connected valves 0 0 adapted bytheir movements to control-the flow of hydraulic-pressure fluid through the ports o 0 A passage 0", connecting the spaces above and below said bushing, delivers the exhaust fluid from the cylinder 0 to the return-pipe 0 A stem 0 extends from the valves 0 c to a piston 0 in a cylinder 0 above the valvechamber 0 V The steam-valve E, which admits steam to one side or the other of the piston 0 to operate the hydraulic valves 0 0 will now be described. The stem 6 of this valve is provided with two valve portions 6 e Within the casing I e These valve portions cooperate with ports 0* 6 leading to opposite sides of the piston 0 Intermediate of these ports the casing e" is provided with a connection 6 for the reception of a pipe 6, which conducts steam to said casing from the main supply-pipe B. Abutments e e on the valve-stern prevent the steam from escaping at the ends of the casing and permit position steam may flowthrough theport 0* into the cylinder 0 where it operates the piston 0 which in turn operates the valves 0 0 to cause the oil or other hydraulic-pressure fluid to flow through the ports 0 0 0 to operate the piston 0 in a direction to open the controlling-valve 0 is shown in the position which it occupies when the controlling-valve is fully open. In Fig. 2 it is shown in the position it occupies when said valve is fully closed.

As will be apparent from an inspection of Fig. 4, there will be a determined range of movement of the valve-stem 6 before the valve portions 6 0 will be moved sufficiently to admit steam through the port 6 to the under side of the piston 0 This range of movement permits the speed of the turbine to increase from the minimum rate at which it is designed that it shall operate to the maximum rate at which it is designed that it shall operate. When this maximum rate is exceeded, the steam-valve will have moved sufliciently to the right to admit steam below the piston 0 through the passage 6 and exhaust the steam above said piston through the ports 6* e. The piston 0 is thereupon elevated, elevating the valves 0 0 to the position shown in Fig. l, admitting hydraulic-pressure fluid to the upper side of the piston e and exhausting that below said piston through the ports 0 0 0 into the return-pipe 0 This causes the controlling-valve to be immediately and fully seated, cutting off the supply of steam to the turbine. As soon as the speed of the turbine has fallen below the desired minimum rate the steam-valve will have moved to the position shown in Fig. 4, admitting steam above the piston 0 depressing said piston and the valves attached thereto and admitting hydraulicpressure fluid below the piston c to elevate the same and fullyand immediately open the valve 0 to admit steam at full volume and pressure to the turbine.

By constructing the hydraulic valve as a balanced valve and leaving such valve free to travel a full stroke whenever steam is admitted to one side or the other of its piston 0 it follows that the controlling-valve c iwill be entirely open as long as the speed of the turbine does not exceed its predetermined maximum limit and that it will be immediately and entirely closed as soon as the speed of the turbine exceeds said limit.

The variation between the maximum and minimum rates of speed at which the turbine shall operate will be determined by the construction of the turbine and the character of the work which it is to perform, and the steamvalve-operating means may be adjusted in any governor valve for any reason fail to operate to cut off the supply of steam to the turbine In Fig. 3 the piston 0 IIO tease? when the speed becomes excessive, I have provided a safety-stop or cut-ofl' device 1; of any approved construction which may be applied to the supply-pipe B B, said stop being put into operation by means of the rod 11, extending into the casing in position to be actuated by the steam-valve when the rate of rotation of the turbine becomes excessive.

By the construction herein set forth I have provided a governor which will automatically open and close the controlling-valve whenever the predetermined minimum and maximum limits of speed at which it is designed the turbine shall operate are exceeded. \Vhen the maximum speed is exceeded, the controllingwalve 0 will be immediately and absolutely closed. hen the speed falls below the desired minimum limit, the controlling-valve will be immediately and entirely opened, thereby admitting steam or other pressure fluid at full pressure and volume. This permits me to employ a free section through the blades and buckets of from two to four times as great as may be employed where the regulation of the speed of the turbine is accomplished by throttling. l/Vhenever, therefore, pressure fluid is admitted to the turbine, it is under conditions which insure the most economical and eflicient operation of the same. Vhenever the speed of the turbine exeeeds the predetermined maximum limit, no pressure fluid whatever is employed therein and the controlling-valve will be open to admit such pressure fluid only when it becomes necessary to restore the speed of the revolving parts. It is obvious, therefore, that great economy in the use of pressure fluid must follow.

While] have shownand described a hydraulic motor for operating the controlling-valve, I do not propose to limit myself to the employment of such motor except as such limitation may be embodied in the claims hereto appended, as it is obvious that such motor may be operated by any means other than the pressure-fluid supply to the turbine and still be within the spirit of my invention.

Having described my invention, I claim I. The combination, with a turbine, of a supply-pipe therefor, a valve in said supplypipe, a governor for said valve, said governor comprising means for fully opening and fully closing said valve when the speed of the turbine falls below or rises above the predetermined limits at which it is desired said turbine shall operate, substantially as described.

2. In a turbine, the combination of a supplypipe for pressure fluid, of a valve for controlling the supply of such fluid to the turbine, and means, operated by the speed of the turbine, for maintaining said valve entirely open until the turbine exceeds the predetermined maximum limit of speed at which it is designed that it shall operate and for thereupon entirely closing said valve, substantially as described.

3. .In aturbine, the combination of a supply pipe for pressure fluid, a valve for controlling the supply of such fluid to the turbine, at governor for said valve, and means dependent upon the speed of the turbine for causing said governor to immediately fully open and fully close said valve when the turbine falls below or exceeds the predetermined limits of speed at which it is desired that it shall operate, substantially as described.

4. In a turbine, the combination of a supplypipe for pressure fluid, a valve for controlling the supply of such fluid to the turbine, a piston for operating said valve to open and close the same, means comprising a piston for admitting pressure fluid to one side or the other of said first-named piston, and means operated by the speed of the turbine for moving the second piston a full stroke in one direction or the other only when the speed of the turbine exceeds or falls below the predetermined limits at which it is desired it shall operate, substantially as described.

5. In a turbine, the combination of asupplypipe for pressure fluid, a valve for controlling the supply of such fluid to the turbine, a piston for operating said valve to open and close the same, a cylinder for said piston, a valvecasing attached to said cylinder having ports for admitting pressure fluid to opposite sides of the piston to actuate the same, a valve for said ports adapted by its movement to admit pressure fluid to one or the other of said ports, a piston connected with said valve for operating the same, a cylinder for said latter piston, a valve-casing attached to said cylinder and provided with inlet and exhaust ports connecting with both sides of said piston, a valve in said CZISIl'lg' controlling said ports, said valve being operated by the speed of the turbine, substantially as described.

6. In a turbine, the combination of asupplypipe for pressure fluid, a valve fol-controlling the supply of such fluid to the turbine, a piston for operating said valve to open and close the same, means for admitting pressure fluid to one side or the other of said piston, means comprising a piston for operating said lastmentioned means, means for operating said last-mentioned piston, said means comprising a cylinder, a valve-casing having inlet and exhaust ports leading to either side of said piston, a valve in said casing controlling said inlet and exhaust ports, a stem extendingfrom said valve, and a device operated by the speed of the turbine and connected with said stem, substantially as described.

7. A turbine having an inlet for pressure fluid, a valve in said inlet for controlling the flow of such fluid to the turbine, a motor for operating said valve, means for supplying said motor with fluid under a suflicient pressure to operate said valve in opposition to the pressure of the fluid supplied to the turbine, and means operated directly by the pressure fluid supplied IIO to the turbine for controlling the flow of such fluid to the motor, substantially as described.

8. A turbine havingv an inlet for steam or other pressure fluid, a controlling-valve in said inlet, a hydraulic motor connected with said controlling-valve, means for regulating the flow of pressure fluid to said motor, means for operating said regulating means by the pressure of the fluid-supply to the turbine, and means for controlling the operation of said last-mentioned means in accordance with the speed of the turbine, substantially as described.

9. A turbine having an inlet for steam or other pressure fluid, a controlling-valve in said inlet, a piston connected to said controlling-valve, a valve for admitting hydraulic pressure fluid to one side or the other of said piston, and means for operating said valve directly by the steam or other pressure-fluid supply to the turbine, substantially as described.

10. A turbine having an inlet for steam or other pressure fluid, a controlling-valve in said inlet, a piston connected With said controlling-valve, a valve adapted by its movement-to admit hydraulic pressure fluid to one side or the other of said piston, means for operating the latter valve by the pressure of the steam or other fluid-pressure supply to the turbine, and means for operating said lastmentioned means by the speed of the turbine, substantially as described.

11. A turbine having an inlet for steam or other pressure fluid, a controlling-valve in said inlet, a motor attached to said controlling-valve for operating the same, a forcedfeed lubricator driven by said turbine, and means for operating said motor by the lubricator fluid. substantially as described.

12. A turbine having an inlet for steam or other pressure fluid, a controlling-valve in said inlet, a motor for operating said controlling-valve, a forced-feed lubricator driven by said turbine, means for operating said motor by said lubricator, and means for controlling said motor-operating means by the pressure of the steam or other pressure-fluid supply to the turbine, substantially as described.

13. A turbine having an inlet for steam or other pressure fluid, a controlling-valve in said inlet, a motor for operating said controlling-valve, a forced-feed lubricator driven by said turbine, means for operating said motor by the lubricator fluid, and means for controlling said motor-operating means in accordance with the speed of the turbine, substantially as described.

1a. A turbine having an inlet for pressure fluid, a valve in said inlet for controlling the floW of such fluid to the turbine, a motor for operating said valve, a forced-feed lubricator driven by said turbine. and means controlled by the speed of the turbine for operating said motor by the lubricator fluid only When the speed of the turbine falls below or exceeds the predetermined limits at Which it is desired that'the turbine shall operate, substantially as described.

15. A turbine having an inlet for pressure fluid, a valve in said inlet for controlling the flow of such fluid to the turbine, a piston for operating said valve, a forced-feed lubricator driven by said turbine, and means controlled by the speed of the turbine for supplying lubricator fluid to opposite sides of said piston only when the speed of the turbine falls below or exceeds the predetermined limits at Which it is desired that the turbine shall operate, substantially as described.

16. A turbine having an inlet for steam or other pressure fluid, a controlling-valve in said inlet, a motor for operating said controlling-valve, a forced-feed lubricator driven by said turbine, means for supplying lubricating fluid from said lubricator to said motor to operate the same, means for regulating the flow of such lubricating fluid to the motor, means for operating such regulating means by the pressure of the steam or other pressure-fluid supply to the turbine, and means dependent upon the speed of the turbine for operating said last-mentioned means, substantially as described.

17. Aturbine having an inlet for steam or other pressurefluid, a controlling-valve for said inlet having a piston connected therewith,

a forced-teed lubricator driven by said turbine, means for admitting lubricator fluid to the opposite sides of said piston, a valve for regulating the flow of lubricator fluid to said sides of the piston, a motor for operating said valve, and means for supplying turbine pressure fluid to said motor to operate the same, substantially as described;

18. A turbine having an inlet for pressure fluid, a controlling-valve for said inlet, a motor for operating said controlling-valve,means for operating said motor by hydraulic pressure fluid, valve mechanism for regulating the flow of hydraulic pressure fluid to said motor, a motor for operating said valve mechanism by the turbine pressure fluid, and means dependent upon the speed of the turbine for controlling the floW of such turbine pressure fluid to such last-mentioned mot-or, substantially as described.

19. A turbine having an inlet for pressure fluid, a controlling-valve for said inlet,amotor connected with said valve, means for supplying hydraulic pressure fluid to said motor, means comprising a piston for regulating the flow of hydraulic pressure fluid to said motor, means for supplying turbine pressure fluid to opposite sides of said piston, a valve for controlling the supply of such turbine pressure fluid to said piston, said valve being operated by the speed of the turbine, substantially as described.

20. In a turbine, the combination of a pipe for supplying pressure fluid to said turbine, a valve for controlling such supply to the turbine, a motor for operating said valve, means for supplying hydraulic pressure fluid to said motor, a valve for controlling the supply of such hydraulic pressure fluid to said motor, a piston for operating said valve, a valvechest for admitting pressure fluid at one side or the other of said piston, a pipe connecting said valve-chest with the supply-pipe of said turbine, and a valve in said chest operated by the speed of the turbine to admit pressure fluid to one side or the other of said piston, substantially as described.

21. A turbine having an inlet for pressure fluid, a valve in said inlet for controlling the flow of such fluid to the turbine, a hydraulic motor for operating said valve, and means, controlled by the speed of the turbine, for operating said motor to open and close said valve only when the speed'of the turbine falls below or exceeds the predetermined limits at which it is desired that the turbine shall operate, substantially as described.

22. A turbine having an inlet for pressure fluid, a valve in said inlet for controlling the flow of such fluid to the turbine, a piston for operating said valve, and means, controlled by the speed of the turbine, for admitting hydraulic pressure fluid to' opposite sides of said piston only when the speed of the turbine falls below or exceeds the predetermined limits at which it is desired that the turbine shall operate, substantially as described.

23. In a turbine, the combination of a supply-pipe for pressure fluid, of a valve for controlling the supply of such fluid to the turbine, a motor for operating said valve, means for supplying pressure fluid to said motor to cause it to open and close said valve, a valve for controlling the flow of such motor-actuating fluid, a piston for operating said valve, and means dependent upon the speed of the turbine for supplying turbine pressure fluid to said piston, said valve for controlling the flow of motor fluid being entirely disconnected from all mechanical connection with any of the other parts of the turbine, substantially as described.

24. In a turbine, the combination of a supply-pipe for pressure fluid, a valve for controlling the supply of such fluid to the turbine, a piston for operating said valve to fully open and fully close the same, means for supplying pressure fluid to one side or the other of said piston, a balanced valve free from all mechanical connection with the turbine and controlling the supply of such fluid to the piston, a piston for operating said valve, means for supplying fluid to one side or the other of the last-mentioned piston, and means operated by the speed of the turbine for controlling the flow of pressure fluid to said lastmentioned piston, substantially as described.

In testimony whereof I hereunto aflix my signature in the presence of two Witnesses.

EDi/VARD CHESHIRE.

Vitnesses:

LUGIAN R. WVORDEN, JAS. F. GRIFFIN.