US712593A - Automatic governor for turbines. - Google Patents

Description

No. 7l2,593. Patented Nov. 4, I902.

A. O. E. RATEAU.

AUTOMATIC GOVERNOR FOR TURBINES.

(Application filed m 20, 1,902.) (No Model.) 2 Sheets- Shani QUNITEDSTATES MOND R TEAmfa citizen? of thejRepnblicofv France, residing at Paris, France, have in vented certain new and useful Improvements l which the following is a specification. r a r anism. I 1 e Iileretoforeinthe governing of steam orfgas r e e n cation for patent, Serial No. 70,438, filedlby in thearrangement is; thatiwhen onlysmall quantities ofsteamare passing through the s much less than the pressure at the boilers,

To be efiicient, the regulation of the distribulicl l e fl'ei i s v i s r te;1 shantysonata Be itknown that LAUGUST OA ILLEEo in Automatic Governors fora Turbines,; of

. My invention has relation to a mechanism for automatically governingsteam or gas bur bines, andin such? connection it relates to the construction and arrangement ot such amech tu rbinescertaindifficulties have arisen,which difficulties it is thebbject of my'presentim vention to overcome." Thus in formergov erning meansa valve throttling thesteamim mediately beforeitstinlet into the turbine is" placed under the control of a centrifugal gov ernor,or, as hereinafter designated,a 5 speed; measurer. This arrangement is convenient j and perfect in action. One defect, however,

turbine the initial pressure at the inlet is and hencea portion of the pressure of the steam is lost withoutany-compcnsating advantage. When condensing turbines it are used, this loss is minimized, but it still exists, and it is therefore desirable to arrange the parts in such a manner that the initial pressure may be kept as high as possible. For this purpose obtnrators or shun-elf slides are. arranged with reference to the bladesdistributing the fluid to the cel'ls of-the turbine in such a manner that the inlets to'a greater or lesser number of blades may be closed, as required, andoperate as in" hydraulic turbines. The controlling of the distributers has already been devised; but in this instance the distribnters have been regulated manually.

ters should beunder the automatic control of the speed-nieasurer, without;however, thereby causing periodic oscillations or variations of speed. t t

In the arrangement embodying my invention, as will be hereinafter more fully described, the governing of-the turbine through the inlet-valve for the motive fluid is still used,

@Au usrnchiiittn I D. R EAU,or jrhais;Felines tervals.

because it has the advantage of being both ei tf No. riaseaseteu notenibel iieoa saith m 108,159. ui'om ciau t rapidandcertain. I nadditiom' however, the

speed-measurer is caused toact at thesame time upon o'ne or more obturators in fsuchea manner that these obturators opener close e the inlet to the blades distributing themotive fluid in the turbines, according as moreor less power isrequired. The rapidity of the move ment ofihe obturators isso calculatedas to. avoid periodic disturbances orvspeed variations, wjhich would result, if carebe nottaken, where the two governing means do notact simultaneouslyn It has beendescribed a previous applimeunder date of August 1,1901, how it is a momentary increase inpower by means of an auxiliary pipe directly admitting acertain fquantity of more or less expanded additional steam toa moving wheel, the position of which wheel being higherup in the series of wheels, according to the more orless increased" power required. In the mechanism described in said previous application it was proposed to open by hand the cock or valve placed the best possible conditions of efficiency. To

attain this object, the travel of the speedmeasurer is divided into three portions or in- In the middle portion or interval, which maybe as small as desired,the speedmeasurer acts only upon the valve for the inlet of steam, and hence governs solely by throttling. In the first portion, corresponding to the range ofhighest speeds of the speedmeasurer, the valve for the inlet of steam continues to be closed by the speed-measurer and at the same time starts into operation a mechanism which operates the obturator or obturators of thedistributi ng-blades of the turbine. In the last portion, corresponding to therange of lowest speeds, the speedmeasurer sets into operation a mechanism which controls the obtur'ator of the surcharge-pipe. The mech-,

anisms for operating both series of obtura possible to produce in a 'multicellular turbine 1 of the usual centrifugalftype'.

stance, as water or oil under pressure, steamor compressed air. In general oil isprefer, able, althoughelectricity may be applied directly in the form of a motor for operating Th'enature and scope of my invention will,

be more'fully understood from the following description, taken in connect on with the accompanying drawings, forming part hereof, in which t Figures 1 and 1 represent when combined a diagram matic view of a mechanism'embodyin'g main features of my invention. Fig. 2 is a side elevational view of a turbine with the governing mechanism appliedthereto. Fig. 3 is a vertical sectional view of a distributer by means of which four blades and their obturators may be governed, and Fig. 4 is a View illustratinga modified form of the levers-connecting the governor or speed-measnrer with the remaining portions of the apparatus.

Referring to Figs. 1 and 1 of the drawings, 1 represents the governor or speed-measurer The steaminlet valve 2 is governed directly by this speed-measurer. 3 and 4 are cylinders which govern'the inlet 0tsteam or motive fluid to the obturator- pistons 22 or 19. The obturator 5 for the turbine-blades is in the form of a slide. The surcharge-pipe 7 leads steam to a blade higher in series than the blade to which steam from the valve 2 is delivered. The speed-measurer 1 acts upon a lever 8, pivoted at 9 and rigidly connected by means of levers and intermediate pins 10, 11, and 12 to the valve-l3, which throttles the steam passing from the steam-chest 14 toward the turbine more'or less. The valve 13 consists ofa plain ring sliding with soft friction in the cylindrical box which surrounds it and is guided by the upper port-iop of the box. When the ring is moved, its lower edge more or less closes the circular orifice formed in the box through which the steam passes. The pin 15 on the lever 8 acts upon the distributing-pistons contained in the cylinders 3 and 4. It pushes one or the other when the axis of the lever 8 passes beyond the position 9 or 9 respectively. The pistons are always pushed back toward the lever 8 by means of small springs contained in the boxes 16 and 17. By this arrangement the lever of the speed-measurer acts solely upon the valve 13 when it is between the positions B and C and continues to act upon the valve when pushing one or the other of the distributingpistons. It is only checked by the small effect necessary to push the pistons and overcome the small resistance of the springs. The speed-measurer may therefore on the occasion of a sudden disturbance in the steam act as rapidly upon the valve as if the supplementary method of governing did not exist. This piston contaned in the cylinder 4 distributes oil through the pipe 18 to the cyl- Fig. 2 shows theapplication of the arrange-' ment to-a turbine. 2 is the steam-inlet valve,

governed by the governor 1 and the oscillatingshaft-Q. a, Z) is the surcharge-pipe. The pistons contained within thecylinders 3 and 4 are arranged one on each side of the pin 15, which is keyed upon the shaft 9 of the valve. 27. is the cylinder by means of which the 0bturator closing the inlet to the bladesis operated, and 22-the cylinder operating the obturator 26 of the surcharge-pipe. In'the pre cedingexam ple a single obturator is shown, which closes in succession the distributing: blades of the turbine. It would also be possible to act upon separate obturators, which are closed one after the other.

Fig. 3 shows a distributer by which four blades, for example, are governed. The shell ofthedistributer is provided with four holes 29, 30, 31, and 32, arranged in steps and connected by pipes to the different cylinders of the blades. A piston 33 moves in the shell and can uncover one, two, three, or four holes, according to its position. The steam under pressure passes inbeneath the piston through the tube 34, while the other face of the piston is in connection withthe exhaust through 35. The pin on the lever of the speed-me'asurer presses upon the end of the piston-rod 4, when the speed of the machine becomes less. The progessive displacement ofthe pin causes the inlet to the blades to be successively opened. It will be observed that in this case the auxiliary motive fiuid which aids the speed-measurer to open or close the inlet to the distributing-blades is the steam itself.

Returning now to the first arrangement of a rotating obturator for closing the distributor-blades, the piston working the obturator and the piston working the surcharge-valve may, if desired, be govered by the pin on the lover of the speed-measurer-that is to say, the displacement of the piston maybe made to be exactly proportional to that of the pin. For this purpose to each of the pistons is added a supplementary lever 36, Fig. 4, one end 37 of which is jointed to the lever of the speed-measurer that is to say, to the pin 15, Fig. 1*, made double, as is necessary for the special case in question--while the other, 38, is rigidly connected by suitable mechanism to the pistons of the relay to be operated upon-that is to say, in this case to the piston of thecylinder 19, Fig. 1, by the rod a, Fig. 4, and to the piston of the cylinder 22, Fig. 1, by the rod 19, Fig. 4. When the pin and the pisto it.

ton have corresponding proportional displacements, the middle pointc or d of the lever remains stationary. This point is placed in front of the head of the piston 3 or 4. of the distributing-piston of the relay. By this wellknown arrangement of governing the piston connected to the point 38 is made to follow exactly the movements of the end37, for, in

effect, when the piston does not move neither does the point 38, which is rigidly connected This point then serves as a center of rotation for the lever 36 when the pin on the lever of the speed-measurer is moved. The

distributer-piston 3, which follows themovements of the point 0 of the lever 36, therefore opens the admission to the cylinder 19, Fig. 1, in such a manner that the piston which is in the cylinder is moved and takes a position corresponding to that of the end 37. As soon as the piston has arrived at this position the end 38 of the lever 36 is so placed with respect to the end 37 that the point 0 comes to its central position, in which the-piston 3,

closes all the distributing-orifices at the same time. The same operation takes place with the other lever 36, which by the rod 5 is connected to the motor-cylinder 22, Fig. 1 and which by the pointd governs the distributing-piston 4. The points c-and d of the levers are provided with screw-studs in such a manner that their position can be regulated very exactly.

In the drawings there is shown a system of closing the distributing-blades. The obturator is in the form of a circular slide, Fig.1, and there is also described in the preceding portion of the specification an obturator in the form of a piston. My system is of course also applicable to any other type of obtu rator, and hence is not limited to a particular type of obturator, but to an arrangement of placing obturators under the control of the gov- 1. In a mechanism for automatically governing steam or gas turbines, a governor or speed-measurer, a throttle-valve controlling the steam or motive fluid inlet to the turbine and controlled by said speed-measurer, one or more obturators controlling the distribution of the motive fluid in the turbine, and

means controlled by the speed-measurer and arranged to operate said obturators.

2. In a mechanism for automatically governing steam or gas turbines, a governor or speed-measurer, a main inlet for the motive fluid into the turbine, a throttle-valve located in said inlet and controlled by the speedmeasurer, a surcharge-pipe leading motive fluid from the source to one of the turbineblades higher in position than the blade receiving motive fluid from the main inlet, an obturator arranged in said surcharge-pipe, means controlled by the speed-measurer and arranged to operate said obturator of the surcharge-pipe, one or more obturators arranged in the turbine and controlling thedistribution of motive fluid therein, and means controlled by the speed-measurer and arranged to operate the obturators within theturbine.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

AUGUS'IE CAMILLE EDMOND RATEAU.

Witnesses:

PAUL DE MESTRAL, EDWARD P. MACLEAN.

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