US867950A - Regulator for steam-turbines. - Google Patents

Description

No. 867,950. PATBNTED 00T. l5, 1907.

E. G. GROGKBR.

-l REGULTUR FOR STEAM TURBINES.

APPLIoATloN FILED FEB. 12, 190e.

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` PATENTED OCT. 15., 1907'. E. C. GROCKER. REGULATOR FOR STEAMTURBINBS.

APPLICATION FILED PEB. 12, 1906.

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REGULATOR POR STEAM TU-RBINES.v ABPLIOATION FILED 11:11.12, l190e.

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UNITE STATES PATENT OFFICE.

EBEN C. CROCKER, OF SANDUSKY, OHIO, ASSIGNOR TO THE WARREN ELECTRIC MANUFACTURING COMPANY, OF SANDUSKY, OHIO.

"l REGULATOR FOR STEAM-TURBINES.

Specification of Letters Patent.

Patented Oct. 15, 1907.

Application tiled February 12, 1906. Serial No. 300.607.

ol Erie and State of Ohio, have invented certain newand useful Improvements in Regulators for Steam- Turbines; and l do declare the following to be a full, clear, and exact description o the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this specification.

In steam `turbines the variations of speed due to change of load are regulated, through a governor, by throttling the steam. When va series of nozzles is assembled in such an engine lor directing the steam against the moving vanes of the engine, the result oi throttling the entire steam-supply is that cach nozzle is deprived oi that quantity of steam which enables it to work'to the best advantage, and the kinetic energy of the steam is weakened at all the nozzles.

The object oi my invention is to overcome the difficulty here indicated, and, more particularly, to furnish, in an engine of the described character, a structure byl means ol which the steam nozzles of the turbine are arranged in groups, and to supply a valve-mechanism by which such groups of 'nozzles may -be thrown into or out of service, independently of each other, and in succession, without throttlingthe steam, and so that all the steam passing through one or more groups of passages is used at its highest ef'liciency. I attain these objects by means of the devices and arrangement oi parts hereinafter described and shown, and illustrated in the accompanying drawings, in Which- Figure 1 is a central vertical sectional elevation of my engine, taken lengthwise oi the shaft; FigA 2, an end-elevation oi the same seen -from the admission or governor side, Fig. 3, a vertical cross-section on lines Y-Y and Xf-X Fig. l; Fig. 4, an enlarged sectional elevation of one of the balanced valves and its stem and connections and actuating mechanism hereinafter referred to, and Fig. 5, a diagram illustrating the successive operation of the valve-mechanisms hereinafter described.

Like numerals ofreierence indicate like parts throughout the drawings.

In the drawings, l and 2 are frame parts, l being the admission' side, 2 being the exhaust side of the frame. The part l is provided with a hollow ring l to which the steam is admitted, as at 3, the part 2 having a like ring 2 into which the steam is exhausted, escaping, as at 4, to a condenser or to the atmosphere In the meeting faces of the two frame-parts are corresponding opposed recesses. tains the vane-carrying wheel, the movable vanes and On the exhaust side, the recess conr the fixed guide vanes. The recess in the face of the part 1 contains the steam nozzles which direct the steam to the moving vanes.

5 is the engine-shaft having a shoulder 6 and a threaded portion 7. Upon this shaft are secured two diskmembers 8-8 having corresponding recesses in their meeting faces so that the two disks together form a hollow disk of the Width of the series ol movable and fixed vanes. The disk-parts are clamped between shoulder 6 and nut 7 1. The disk-body thus formed is secured to the shaft by key 9. A ring I0 shrunk on the periphery of the disk 8--8 carries the moving vanes 12. A ring orrings l5 fitted and rigidly secured in the circular recess in the frame part 2 carries the series oi fixed vanes 17 interposed between the series of moving vanes. A The exhaust side oi the last series of moving vanes is in communication with opening 4 leading into the hollow ring 2. In the recess in the face of the exhaust side of the frame-part l is a nozzle-ring 18 having the steam passages 19 milled in its peripheral face.- Upon this ring is shrunk another ring 20 which completes and closes the steam passages. The rings 18-20 are se cured in place by flanged rings 2l bolted to the face of the part 1. In the inner side oi the circumferential recess in the face of the frame-part l is a series of pockets 22 which, when the rings 18-20 and 2l are in place, become closed chambers communicating with the inlets of the nozzles 19. These chambers are separated from each other by intermediate radial partitions 23 cast with and forming part of the frame-member. A group oi two or more nozzles 19 is in communication with each of the chambers 22 through openings 24. (See Fig. 3). Each of the pockets 22 is also in communication with the interior oi the steam-ring 1 through holes 22 tapped in the wall between the ring and the pocket. Into each of these holes is-screwed a valvecasing 25 in which is a valve 26, preferably of the balanced type. The valve is provided with a stem 27 which extends out through the front face of the framemember l through a stufling-box 28. A spring 29, interposed between the gland of the stuffing-box and a sleeve 30 secured to the valve-stem, serves to hold the valve normally open. An adjusting stop-nut 31 limits and adjusts the outward movement of the valve-stem.

32 is a stationary ring supported on the ace of the steam ring l" and having in its outer periphery `a grooved ball-race. 33 is another ring having in its inner periphery an opposed grooved ball-race. In these opposed ball-races is a series of balls forming a ballbearing for the ring 33 by means oi which it is permitted to rotate in either direction. In the tace of the ring 33 are formed concentric circular grooves into which are fitted and secured the edges of metal strips' 34, the outer margins of which are, at predetermined intervals, indentedbiasillustrated, as at 35, in Fig. 5. Theuindentations are accurately located and spaced at different points oi the circumference ot the metal strips. The ring 33 is internally toothed, as at 36, in a limited arc of its circumference, (see Fig. 2) forming a rack which meshes with pinion 37. The pinion is connected with and operated by a proper governor which is not shown in the drawings and which, forming no part of this invention, need not be here described.

38 is a lever pivoted, as at 39, on a bracket 4() and which carries at its inner end a roller 4l, placed in proper position to ride upon one or the other of the indented circular cam-strips 34. By providing two con centric cam-strips, I am enabled to make them much smaller and of much less motion than if a single strip were provided ier all the levers and rollers. In the outer end of the lever is a cushion-spring 42 acting on the valve-stein 27 through the short piston 43, and which serves to take excess of pressure after the valve is closed tight.

It will be seen that the inner circle of cams 35 acts upon a series of levers having greater length than the levers which are actuated by the outer cam-strip. The long and short levers alternate.

The operation oi' my device, thus iai' described, is as follows: Steam being admitted to the steam ring lIl passes through open valves 26 into pockets 22 thence through openings 24 and nozzles I9, through alternating series oi moving and fixed vanes and the exhaust ring 2i. When the speed oi' the engine becomes too great, a governor, through the rack and pinion 36737, swings the ring 33 upon its ball-bearing thus bringing the raised portions ol the indented cam-strips 34, one after another, in contact with the rollers upon the levers, lifting the rollers 4l., one at a time, out of the depressions in the camsstrips, thus swinging the levers 38 which thrust the valve-stems inwardly and close the valves 2G. The reverse movement of the ring 33 produces the opposite effect and the valves are successively opened. It will be seen that each time one of the valves is thus operated, a steam pocket 22 is thrown into or out oi communication with the steam ring l1L and a group ot nozzles is thrown into or out ol action It will also be seen that such nozzles as remain iu act ion are operated under a full head oi steam, the velocity ol' which is not retarded by throttling, and that thus the full efficiency oi those nozzles which are in action is at all times maintained.

I have described the steain-ptimkets 22 each as having a group oi two or more nozzles. ln ordinalv practice, this arrangement is found satisl-actory, but when exs treme nicety oi' regulation is required each pocliet may have but one nozzle, the valves and valve controlling mechanisms being modilied accordiuglv Having described my invention, what l. claim and desire to secure by Letters latcnt isf* 1. In an elastic iluid turbine. a hollow ring. a series oi' chambers. valved conntwtions between the rii and thc chambers, stems tor the valves. a rotatable rin, having cam-sections adapted to actuate said valveste1us. devicesv for actuating the rotatable ring. which devices are adapted for connection with a governor. and a serits ot nozzles. each chamber being connected with one or more ol' said nozzles.

2. In an elastic lluid turbine. a rotatable ring. a toothed rack on the ring, a pinion engaged with the rack and adapted for connection with a j overnor. cani-sections on the ring, levers pivotcd on the engine and adapted tor engageu ment with the camfsectious, valves which are actuated by the throw oi' said levers. a series of chambers. a cham ber common to said series o1` chambers said valves bein:

located between said series ot' chambers and said common chamber. and a group ot' nozzles connected with each ol' said series oi chambers.

3. In an elastic tluid turbine. a series ot chambers. a

chamber common to tht.` series ol' chambers. one or a group of nozzles connected with cach ot' said chambers ot' said series, valves which control the passage trom the common chamber to the series ol' chamber and means t'or actuati said valves successively touuirising a rotatable ring ha\ two concentric series otcam-sections. and devices conY nected with the valves and adapted tor engagement willi said cam-sections.

In te :imonv whereot l atlix mv signature in presence ot two witnesses

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