US963881A - Turbine-controlling device. - Google Patents

Description

B. 1?. EHRBABT. commune 1mm.

urn-mum! ruzp mag. 251m. Patented 111111910.

m E S S F. N F. W

ATTORNEY v UNITED STATES PATENT OFFICE.

RAYMOND N. EHRHART. 0F PITTSBUBG. PENNSYLVANIA, ASSIGNOR TO THE WEST- INGHOUSE MACHINE COMPANY, A CORPORATION OF PENNSYLVANIA.

TURBINE-CONTROLLING DEVICE.

Specification of Letters Patent.

Patented July 12, 1911).

To (LIZ whom it may concern:

Be it known that I, RAYMOND N. EHR .rmn'r, a citizen of the United States. and a resident of littsburg. in the county of Allogheny and State of Pennsylvania have. invented a new and useful Improvement in Turbine-Controlling Devices, of which the following is a specification.

This invention relates to elastic fluid turbines, and more particularly to automatic governing means for such turbines.

It. has been customary for some time to provide elastic fluid turbines with what is known as a secondary valve. through which high pressure motive fluid is introduced, as occasion demands, to a part of the turbine which is normally subjected to motive fluid at a lower pressure. This is done for the purpose of increasing the capacity of the turbine.

The object of this invention is the production of an automatic secondary valve for the above purpose which is oi .lmple construc tion and effective and certain in operation. This object I attain in an apparatus embody ing the features hereinafter described and illustrated.

In the single sheet of drawing accompanying this application and forming a part thereof, a somewhat diagrammatic view of an elastic fluid turbine is shown, in COIllll-(P tion with a sectional view of a valve mechanism embmlying this invention.

A turbine rotor 52, comprising a high pres sure drum 3, two intermediate PIOSSUIC' drums 4 and 5 and a low pressure drum (3. is mounted on a suitably jt lll'lltil'l' l shaft 7.

The casing 8 is divided on the ll tll'ltllllill p ane passing through its axis and is pro vided with a steam inlet port 5'. a secondary steam inlet port 10 am an (\llnlast port ll. Each drum of the rotor is provided with a suitable number of annular rows of lliltltri 1'3, which are adapted t coon-rt the energy of the motive fluid, (which for convluiicncc will hereafter be called steam) into rotary motion; between the rows of blades 12 anare arrang d.

mounted on the shaft 7. are arraug -d [c counter alance the end thrust m't-asionvd by drums. iiy ball governor 15, mounted on the casing 8, is operated by the shaft 7 through suitable gears not shown, and is adapted to vary the supply of steam to the turbine in accordance .ith the load demands or speed variation.

A poppet valve 16 is arranged to deliver ire steam periodically, or in otts, to the turbine through a pipe 17 which is connected to the steam port- 9. The duration of the mails, or the amount of steam periodically admitted to the turbine by the valve 16, is controlled by the governor 15. Fulcruiucd on a reciprocating collar 18, which is carried by the governor standard 19 and is actuated by the centrifugal balls 20, is a floati g lever 2i; one end of this lever is attached to an operating eccentric 2:? by a link :23, a lever 24 (which is fulcrinned on a bracket mounted on the casing S} and a link 26; the other end of the lever is colincetcd to a pilot valve 27 by a link 25.

'lbe main or primary admission valve 16 is rovided with a valve chamber 29 which is connec ed to a steam supply pipe 31) and to the pipe. 17. The valve 16 is connected to an operating rod 31 on which is mounted a piston 32 reciprocahle within a cylinder 33.

A steam passage 4H, surrounding the stem 33, connects the lower portion of the cylinder 33 with the valve chamber 29, thereby admitting steam into the cylinder which for es the piston against a spiral spring 2H, surrounding the rod 31, and opens the valve 16. An exhaust passage 35 connects the cylinder 33 with a chzuubor 36 which is connected to the atmosphere or to a condcus'i'i' by a pipe 37. The pilot valve 557 is poriodicall rcriprocatcd by the lever '21 and contr ls the exhaust from the cylinder 33, and tho arraugvuu-ut .is such that, when the turbine is running the pilot. valve periodically exhausts the steam fr m the cylinder 33 and thereby n-:-imli -all rinse the valve 16.

Sin-1c tho opt-rating lr cr "it is luh'rumcd on the. collar lH. Ibo thl'n' o? the pilot valve, relative to the passage 3 \a"ics with the -cu o. the turbin .mn [.upt't'l'ul during nular rows of stationary (lH'lf'liHQ ram-s l Dummy pistons l-l. suitably i which liu- P.\ll:l'l'-'l pus-ago is open is inrrcased or dw'l'vu 'ml n: :m-ordurm: with the loud (i lll:llill-'. hon the l ad ol: the tur- Lino l. so grout lbal it slow-s down an the steam pressure on lilo several working ltlii the valve 15 does not reach its seat and steam is admitted to the turbine n a. continuous stream.

A secondary valve 38, adapted to control the steam supplied to the secondary admission port 10, is located within a valve chamber 39, which communicates with the primary admission port 9 through a passage -10 and the secondary admission port 10 through a pipe 41. The valve 38 is cylindrical'and is adapted to reciprocate within its chamber, which is formed with a cylindrical extension 42, which is supplied with steam through a pipe 43 connected to the steam supply pipe 30. The flow of steam through the pipe 43 and into the extension 42 is controlled by a needle valve -14. An exhaust port- 45 connects with the atmosphere or with a low pressure stage of the turbine through a suitable pipe 47. and is provided with a. needle valve 4c. The How of steam through the valves t and 46 is so adjusted that the pressure in thc txltllmitlll 42 of the valve chamber will be some predetermined amount lower than the initial pressure of the steam in the pipe 30.

As has been described, the main or primary admission valve 16 admits steam to the pipe 17 and the annular passage. it) in putts, the duration of which is determined or controlled by the governor. lVhc-n the turbine is working under lightload, the steam admission period of the main valve is very short and consequently the small amount of steam admitted to the turbine will exert little pressure in the passage 40 from which it is discharged into the high pressure stag" of the turbine through suitably arranged nozzles. Asthe load on theturbinc increases the steam admission period lengthens and the velocity of the increased amount of steam passing through the passage 40 will be somewhat decreased by the limited discharge areas of the steam nozzles, and consequently the pressure exerted by the steam in the passage 40 increases until for some predetermined loadit is sutlicicnt to overcome 'the adjusted pressure in the extension 42 and lift the secondary valve 38, thereby allowing high pressure steam to enter the intermediate stage of the turbine. As the valve 16 is constantly pulsating, the valve 38 will be subjected to periodic increases of pressure, and, when operating will pulsate synchronously with the valve 16 and admit high pressure steam to the intermediate portion of the turbine in putts. The passages 17 and 40 may be so designed. however, that for some predetermined load on the turbine the valve 38 will :supply the intermediate section of the turbine with a constant stream of high pressure steam.

llaving now described nay in\"-ntion.what; l claim as new and useful and desire to secure by Letters Patent is:

1. In an elastic fluid turbine having an initialstage fluid inlet, an intermediate-stage fluid inlet, a valve controlling the intermediate-stage fluid inlet sensitive to the variations in pressure in the initial stage, and means whereby said valve is held closed by tlnid pressure, until the pressure in said initial stage is sufiicient to overpower said closing pressure.

2. In an elastic fluid turbine having an initial-stage fluid inlet, an intermediate-stage tlnid inlet, a valve controlling the intermediate-stage tlnid inlet sensitive to the variations in pressure in the initial stage and means whereby said valve is held closed by an adjustable fluid pressure until the pressure in said initial stage is sutlicient. to overpower said adjusted pressure.

8. In an elastic fluid turbine having an initial-stage tlnid inlet and an intermediatestage tlnid inlet, a governor-controlled valve controlling the initial fluid inlet, mechanisms whereby said valve is caused to pulsate the fluid passing it, a valve controlling the intern]: diate-stage tlnid inlet, means whereby said valve is held closed by an adjustable tiuid pressure until the pressure in the intermediate stage exceeds a predetermined pressure.

4. In an elastic fluid turbine having an initial-stage fluid inlet and an intermediatestage tlnid inlet, a governor-controlled valve controlling the initial tlnid inlet, mechanisms whereby said valve is caused to pulsate the tlnid passing it, a valve controlling said internicdiate-stage fluid inlet, comprising a. piston. a chamber located above said piston, provided with a valved inletportand a valved outlet portand means for admitting a definite amount of tlnid to said chamber and for proportioning the pressure of said tlnid whereby said valve is heldcloscd until the pressure in the initial stage exceeds a ct'llnltl predetermined amount.

In an elastic tlnid turbine, an initial stage tlnid inlet, a secondary stage fluid inlet, a valve controlling the initial stage inlet, and means subjected to tlnid pressure and sensitive to the pressure admitted by said valve for admitting tlnid to said secondary stage tlnid inlet.

1'. In an elastic tlnid turbine, an initial stage tlnid inlet, a sm-ondary stage tlnid inlet, a valve controlling the passage of tlnid through said initial inlet. and a. fluid restrained means, sensitive to the variations of pressure admitted by said valve, for admitt ing fluid to said secondary inlet.

7. In an elastic fluid turbine, a primary stage tlnid inlet, a secondary stage tlnid inlet-,a tlnid restrained valve sensitive to the pressure admitted by said primary inlet for contr lling said secondary inlet.

8. In an elastic tlnid turbine, a primary stage tlnid inlet, a main supply valve eontrolling said inlet, a secondary stage fluid inlet, a fluid restrained valve sensitive to the ressure admitted bysaid main supply valve or controllin the amount of fluid delivered to said secon ary inlet.

9. In an elastic fluid turbine, a primary stage fluid inlet, a secondary stage fluid inlet, a fluid restrained valve for said secondary inlet sensitive to the pressure delivered by said primary stage inlet and means for causin said valve to pulsate.

10. 11 an elastic fluid turbine, a primary sta e fluid inlet, a main supply valve contro ling said inlet, a secondary stage fluid inlet, a fluid restrained valve sensitive to the ressure admitted by said main supply valve or controlling the amount of fluid delivered to said secondary inlet, and means for causing said fluid restrained valve to pulsate.

11. In an elastic fluid turbine having an initial stage fluid inlet, an intermediate stage fluid inlet, a valve controlling the intermediate stage fluid inlet, sensitive to variations in pressure in the initial stage, and means whereby said valve is subjected to a constant closing pressure.

12. In an elastic fluid turbine having an initial stage fluid inlet, an intermediate stage fluid inlet, a valve controlling the interniediate stage inlet, sensitive to variations of fluid pressure delivered by said initial stage inlet, and means for transmitting a closing pressure to said valve, which remains constant during the operation of said valve.

13. In an el. s'tic fluid turbine, an initial stage fluid inlet, an intermediate stage fluid suflicient to overpower said closing pressure,

and mechanisms whereby the fluid passing,

said primary valve is caused to pulsate.

14. In a. multi-stage elastic fluid turbine, an initial stage, a secondary stage, a fluid inlet communicating with said initial Stage, a fluid inlet communicating with said secondary stage, a val ve controlling the delivery of fluid through said initial stage, and a fluid-restrained valve, sensitive to variations of fluid pressure delivered to said initial stage, for by-passing fluid around said initial stage.

15. In a multi-stage elastic fluid turbine, a valve controlling the delivery of fluid to the initial stage of said turbine, and means, subjected to fluid pressure and sensitive to pressure admitted by said valve, for bypassing fluid admitted to said valve around the initial stage of the turbine.

16. In a multi-stage elastic fluid turbine, a governor-controlled fluid admission valve, and a fluid-restrained valve, sensitive to fluid pressure admitted to a stageof said turbine, for by-passing fluid around said stage and delivering it to a stage of lower pressure.

17. In a multi-stage elastic fluid turbine, a fluid admission port delivering fluid to said turbine, a fluid restrained valve, sensitive to fluid pressure admitted to a stage of said turbine, for by-passing fluid around said stage and delivering it toa stage of lower pressure. and means wh reby the fluid passing said valve is caused to pulsate.

In testimony whereof, I havehereunto subscribed my name this 27th day of De cember, 1905.

RAYMOND N. EHRHART. lVitnesses CHARLES \V. McGnEE, Jun. S. GREEN.

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