US1240743A

US1240743A - Elastic-fluid turbine.

Info

Publication number: US1240743A
Application number: US10527116A
Authority: US
Inventors: Louis C Loewenstein
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1916-06-22
Filing date: 1916-06-22
Publication date: 1917-09-18
Anticipated expiration: 1934-09-18

Description

L C. LOEWENSTEIN.

ELASTIC FLUiD TURBSNE.

APPLICAUON HLED JUNE 22. 1916.

1 ,240,743 Patented Sept. 18, 191?.

29 7 Inventor, LOUiS C. Loevvenstein,

{UNITED STATES I Ol TIS C. LOEWENSTEIN, OF LYNN, MASSAC HUSETTS ASSIGNOB '10 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELASTIC-FLUID TURBINE.

' Application filed June 22,

To all whom it may concern:

Be it known that I, Louis C, Lonwnns rnrN. a citizen of the Unit-ed States, rcsidbig at Lynn, in the county of Essex, State of lllassachusetl's, ha invented certain new and useful In;plovruuents in Plastic-Fluid Turbines. of which the following is a spcci-- fication.

The present inventi n relates to elastic l0 thud turbines, and particularly to turbines inning a conduit leading from an intermediate stage through which motive fluid ,is adapted to pass. Such a conduit may lie torcxtractin steam for industrial purposes, or for use as an auxiliary exhaust when the turbine is operating iioincoiidensirig. In such turbines when operating non-condensing, which means that oneor more of the low pressure. stages are running idle, there is danger of overheating the last stage wheels which may result in considerable damage. This heating is due to the rotation .,,losses of the wheels continually heating the steam atmosphere surrounding them. This may occur when for any reason the condenser vacuum is lost, as when the operator shuts down the condenser when the unit is we -king with all the steam extracted in any earlier stage.

The object of the presentinvention is to prdvidc an improved means for obviating this danger, and to this end I provide. an

automatic arrangement which will insure under all conditions the circulation of elastic-fluid through the final stages of the machine when the wheclstherein are runningiii For a consideration of what I believe, to

be novel and my invention, attention 1s (11- rected to the accompanying specification and the claims appended thereto,

In the accompanying drawing, Figure .1

is a sideeleVation partly in section of a portion of an elastic fluid turbine illustrating my invention, and Fig. 2 is a section talienjon line 2-2,:Fig. 1.

Referring to the drawing, 5 indicates the casing of an elastic fluid turbine and 6 the shaft thereof upon which mounted the lmcket Wheels of themachine. In the prescnt insta ncc tl1;e machine isshown being "stee -Ja on Stea s rsl ee fls a 7, 0 he i t i ing o iic c s ii i h e i ioii l an each of the succeeding stages is a single Specification of Letters Patent.

Patented Sept. 18, 1917.

1916. Serial No. 105,271.

wheel 12 having a single row of buckets 13. Elastic fluid admitted to the high pressure and of the machine by a conduit 14', and after passing through the sl'iccessive stages exhausts into the head 15 which is connected to a col'idenser 15 as is usual. 16 indicates the nozzles through which elastic fluid is admitted to the first stage. and l7, l8 and '19 indicate thinozzles of the remaining, stages, uhieh nozzles are located in the diapln'agms. Connected to the second stage is a conduit .20 through which elastic fluid may be ex tracled. This conduit may be for the pur pose of connectingtho second stage to atmosphere so that the machine may operate non-condensing, or it may be for the purpose of extracting steam for industrial purposes. 1 preferably provide a ring valve mechanism for controlling the'fiow of elastic fluid from the second stage to the third, and in the present instance it is shown as comprising a fixed member 21 having openings 22 therein, and a movable member 23 having openings 24. The movable member is adapted to be turned circumferentially to bring theopenings 24 into and out of aline-ment with the openings 22 to regulate the flow of elastic fluid from the second stage to the next succeeding stage. When the machine is used for extracting elastic fluid for industrial. purposes, it is desirable to maintain a constant pressure in the extraction stage, and to this cnd thering valve is placed under the control of a. pressure operated ap-. paratus, which apparatus responds tothe pressure existing in the extraction stage, In the present. instance, as shown in Fig. 2, the movable member 23 is provided with a gear segment 25 with which engages a short rack 26 connected to the piston 27 of a fluid actuated motor 28. This fluid actuated motor is under the control of asuitable pressure responsive device, in the present instance shown in. the form of a diaphragm 29, which isconnectcd to the pilot valve 30 'ofthe motor through a bell crank leyer 31 rod 39, floating lever 3f3, and rod 34,.the floating lever being connected to the piston rod. '35 through an arm 36. The under side i of thediaphragm 29 is connected by a suit- .able ,pipe 37 to the pointat which it is de- .s di q m i t .m tsa ressur u y .y 0 I RS aveli iii oi v'iidi 'anism for the ring valve, such as is well s it If w Il di 1-. ype (i sri lie iibiitrri "initia c known, and further details of the structure and operation is believed to be unnecessary.

The ring valve when utilized, is so arranged that it can never completely shut oil communication between the extraction stage and the next succeeding stage, and to this end one of its openings 22 as indicated at 22, Fig. 2, is made larger than the others so that ,when the ring valve is moved to its final closed position an opening is still left through which a sufficient quantity of elastic fluid may flow from the extraction stage to the succeeding stages to give a circulation, such as will prevent overheating of the wheels running idle in such stages.

However, it may happen that the condenser may fail or is shut down so that the vacuum is lost. Under these circumstances there would 'not be suiiicient difference in pressure between the extraction stage and the final stage to give such a circulation through the final stages as would be required to prevent overheating, and to take care of this I provide a special automatic valve mechanism which will admit elastic fluid at a pressure higher than that of the extraction stage to the final stage or stages of the machine, from which it will circulate backward through the final stages to the extraction stage. This automatic valve mechanism is arranged to'be controlled by the pressure in the final stage, or when a sta e valve, as ring valve 23 is used, by both the position of the ring valve and the pressure in the final stage, t. e., .the condenser pressure, and is such that should the vacuum of the condenser be lost or in the case when stage valve is used, should it be lost at a time when the stage valve is closed, elastic aid will be automatically admitted either rom a primary source through a reducin alve, or from the first stage, to the fina tage or stages of the machine. The conenser vacuum may be lost, for exam 1e, dhe .to the condenser being purposely shut down by the operator or due to failure of the apparatus.

In the present instance I have utilized two valves as indicated at 38 and 39, which valves together control the flow of elastic fluid from a primary source through conduit 40am], reducing valve 41, or from the first stage through conduit 42 and non-return valve 43 to the

branchconduits

44 and 45 which lead respectively to the two last stages of the machine. The valve 38 is biased toward open osition by a spring 46 and isnormally held closed by a cam surface 47 on the rack 26 which engages the end .first stage pressure will of a pin 48, which in 'turn is connected with the ring valve is closed. Then the ring valve is open the cam surface 47 engages the pin 48 to close valve 38. The valve 39 is biased toward closed position by a. spring 51 and is adapted to be opened by a pressure operated device, here shown in the form ofa diaphragm 52 arranged in a casing 53. The casing 53 beneath the diaphragm is connected by a pipe 54 with the exhaust head J of the machine. It will thus be seen that the pressure normally existing under the diaphragm 52 is that of the final stage; i. 0., the condenser pressure.

During normal operation, when the machine is operating condensing, valve 39 is held closed by the spring 51, such spring being sufliciently strong to seat the valve against the pressure then existing under the diaphragm 52, i. e., the condenser pressure, while the valve 38 may be open or closed according to the position of the ring valve. In any event, so long as the vacuum is maintained there will always be suilicient circulation of elastic fluid through the final stages of the machine to prevent the wheels therein overheating, since the ring valve when closed does not completely shut off the flow of elastic fluid through the final stages. Should, however, the vacuum be lost, the pressure conveyed to the under side of diaphragm 52 by pipe 54 will be such as to open the valve 39 against the spring 51. If now the ring valve should be closed, then the valve 38 would also be openedas already explained. This then would admit elastic fluid either from the pipe 40 through reducing valve 41, or from the first stage of the machine through pipe 42 and non-return valve 43, to the

conduits

44 and 45 through which it wouhi' flow to the final stages of the machine and thence backward through the machine and through opening 22 to the extraction stage and out through pipe 20. This will, therefore, provide a circulation of elastic fluid through the final stages of the machine and protect the wheels- Ordinarily the suflicicntly high so that the elastic fluid may be taken from it, but if it is not, then it may be obtained directly from :1 pi e 40 and reducing valve 41.

t will be understood that when my in vention is carried out in connection 'with a machine not provided with a stage valve, as the ring valve shown, then the valve 38 will be omitted, the flow of elastic fluid to the final stage or stages throu

h conduits

44 and 45 being then wholly an or the con 'trol of valve 39.

-In accordance with the provisions of the patent statutes, I have described the principle of operation of m invention, together with the apparatus w job I now conidor to represent the best embodiment thereof;

therein from overheating.

rimary source; through the machine, and

but I desir to have it understood that the apparatus shown is only illustrative, and that the imention can be carried out by other means.

\Vhat I claim and desire to secure by Let ters Patent ot' the United States, is:

1. The. combination ot. a turbine having a conduit leading from an intermediate stage. a condenser into which the tinal stage exhau ts, a stage valve controlling the passage of steam from such intermediate stage to the next lower stage, said stage valve being arranged so that it cannot entirely shut oil the flow of elastic fluid through the turbine. conduit means for supplying elastic fluid to a stage of the machine low er than such intermediate stage. and 'alve means which is under the control of the stage valve and the pressure existing in the linal stage of the marhine for admitting elastic lluid through the conduit means to the tinal stage when the condenser vacuinn is lost. and the stage valve is closed.

2. The combination of a. turbine having a conduit leading: from an intermediate stage, a condenser into which the final stage exhausts, a stagewalre controlling the pas sage of steam from such intermediate stage to the next lower stage, said stage valve being arranged so that it cannot entirely shut oft the flow of elastic fluid through the turbine, conduit means for supplying elastic tiuid to ach stage of the machine lower than. such intermediate stagtn aml valve means which is under the control of the stage valve and the pressure existing in the linal stage of the machine for admitting elastic tluid through the conduit means to the [inal stage when the condenser vacuum is lost and the stage valve is closed.

:1. The coinbiinition of a. turbine having a ttfl ltllllt leading from an intermediate stage, a condenser into which the final stage exhausts. a stage valve controlling the passage of steam fromsuch internnaliate stage to the next lower stage, said stage valve being arrai'igcd so th'atlil; 'anuot entirely shut oil the tlow of elastic fluid through the tarbine, conduit means for supplying elastic tluid to one or -niore ot the final stages of two" valves in said conduit means; one of which is zimder the control of the'stagcvulneand is opened when the stagevalve closed, and the, other of which is under tlieiiontrol of the pressure exit-tin in the condenser and is opened in said pipe. and means controlled by when said pressure riiaches a predetermined high value for controlling the flow through said conduit means.

4:. The combination of a turbine having a conduit leading from an intermediate stage, a condenser into which the final stage exhausts, a stage valve controlling the passage of steam from such intermediate stage to the next lower stage, said stage valve being; a1 anged so that it cannot entirely shut ofl the flow of elastic fluid through the turbine lluid actuated means responsive to the pressure of said intermediate .tege for regulating the stage valve, a conduit connectingthe first stage of the machine to the final stage. and valve means under the control of the stage valve and the pressure in the tinal stage for admitting elastic uid through said conduit when the stage valve is clo ed and the condenser vacuum is lost.

5. The combination with a turbine havin; a conduit leading from an intermediate stage and a condenser "mo which the final stage exhausts, of means for introducing elastic tluid from an earlier stage of, the

machine into one or more of the lower stages of the machine when the condenser vacuum is lost. said means being controlled by the pressure of the condenser.

(i. The combination with a turbine having a conduit leading from an intermediate stage aml a eondenser into which the, final stage. exhausts. of a ,pipe connecting an initial stage of the machine to one or more of the final stages, a normally closed valve the pressure in the condenser for opening said valve.

7. lhe combination with a turbine having a conduit leading from an intermediate stageand a condenser into which the final stage exhausts. of means controlled by the pressure in the condenser for introducing elastic tluid of of said intermediate stage to one or more of the (bud stages of the machine when the condenser is shut downand the wheels in such linal stages are runuiugidle, whereby such elastic Ilnid may circulate backward through the idle stages of the machine to preventthe wheels therein from overheating.

l n witness whereof. I have hereunto set my hand this l th day of June, 1916.

u l u i s o. LOEWENSTEIN.

a pressure higher than that