US1021226A - Controller mechanism for turbines. - Google Patents

Description

J. WILKINSON.

CONTROLLER MECHANISM FOR TURBINES.

APPLICATION FILED 001212, 1911.

1,021,226. PatentedManZG, 1912.

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UNITED STATES PATENT OFFICE.

3mm WILKINSON, SOHENECTADY. NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A' CORPORATION 01 NEW YORK.

To all whom it may concern Be it known'that I, JAMES WILKINSON,

, a citizen of the United States, residin at Schenectady, county of Schenectady, tate of New York, have invented certain new and useful Improvements in Controller Mechanisms for Turbines, of which the following is a specification.

My invention relates to improvements in controller mechanism for elastic fluid turbines wherein a plurality of separate valves are operated to o n and close nozzles by the action of hydrau ic pressure under the control of a governor or hand actuated device.

It is one urpose of my invention to utilize hydraulic pressure, preferably that of oil, for actuating a series of sma l, motors, connected to turbine valves through ower increasing devices, by means of whic but small power is required of the motors to force the valves, with considerable pressure, against their seats or to open them against the ressure when unbalanced. Oil or other liquid, by reason of its inelasticity, responds more direct-1y and positively to the control of the governing devices, than steam or other elastic fluids, thus making the regulating mechanism for the turbine more sensitive and efficient.

It is a'further object of my invention to provide a simple and powerful force pump, preferably a gear pump, for forcing the 011 vor other liquid through a controller device,

here "shown as a nozzle, which discharges the liquid under pressure into one or the other of two controller conduits which lead to a plurality of independent valve motors.

My present invention constitutes an improvement over the controller mechanism described in Letters Patent No. 753,773,

issued to me March 1st, 1904, in that the governing device controls the pressure of the valve actuating fluid on both sides of the differential motor pistons. By this means I dispense with the dead head of pressure under the pistons and maintain a circulation of all the controller fluid which is of particular advantage where steam is 'used, as it reduces condensation.

My invention further contemplates the provision of a resilient valve adapted to be operated by the use of powerful leverage dev1ces between the fluid motor and valve, which devices will act in a manner to retard Specification of Letters Patent. Application filed 0mm 12, 1011. mm m. was.

Patented Mar. 26, 1912.

the travel of the valve at the ing and to hold it under such compression against its seat as to keep the latter pro erly polished and to prevent wear due to lea age of the motor fluid between the valve and its sea My invention further comprises the details of construction and arrangement of parts hereinafter described and illustrated 1n the accompanying drawin s, in which Figure 1, represents a tur ine inpartial side elevation, the casing being broken away.

to show a set of nozzle passages with their controlling valves. The controller mecha' nism for the valves is shown, in vertical sectional view, mounted on the turbine; Fig. 2, is a top plan view broken away of the valve motor casing with its top plate removed, and Fig. 3, is a side view of the toggle mechanism.

Similar reference numerals refer to similar parts throughout.

I have shown my invention applied to an axial flow turbine of the impact type, wherein a series of nozzle passages 1 lead from a supply passage 2 in the head3, and discharge fluid pressure at an angle against a bucket wheel 4. These nozzles may be provided with director plates 5 in their discharge ends. I provide a separate resilient valve for each nozzle passage comprising a spring cup 6 secured to a valve stem 7and adapted to completely, cover the nozzleentrance when closed. These valve stems 7 project through suitably packed openings in the supply head 3 and are connected each point of seat-J to a separate double toggle, operated by a fluid motor.

The toggle actuating mechanism for each valve comprises a pan of oppositely disposed bell crank levers 8 journaled upon a common side 9 sup ortal rigidly in a frame 10, that is provided with bearings 11, between which the several bell crank levers are mounted. These levers are connected at their lower ends through toggle links 12 to cross heads 13 connected to each of the valve stems 7. At their upper ends the levers 8 are similarly connected by toggle links 14 to cross heads 15 fixed to the lower ends of stems 16, which are connected to the valve actuating pistons 17, 18 and 19.

The motors for operating the several valves comprise cylinders 20, 21 and 22,

. provided to formedin a casing 23m'ounted. upon and;

rigidly secured to a plate 24 integral with the frameulO. Through this plate the several stems 16 pass, packing glands 25'bein revent the leakage of fluid from the cy inders above. The plate 24 forms the lower ends. of the several motor. cylinders, their upper ends being formed by ap'lat'e 26 secured to the top of the casing 23;

It being the purpose to illustrate my in- -vention in its simplest form, a series of differential cylinders and pistons are shown which, being subjected to a gradually varying: oontrolled pressure will successively open'or:' close the valves. Three cylinders are shown; the first cylinder as repre .rsenting the extreme at one end of the series, the cylinder 21 as representing the middle cylinder of the series. and the cylinder 22 as representing the other extreme ol' the series. It will be evident that between the cylinders 20 and 22 and the middle cylinder, any desired number of other difierential cylinders of graduall varying proportions may be used. Accor ing to my present invention therefore the controller mechanism may be elaborated to control any desired number of turbine valves. v The controller mechanism for the series of valve actuating motors comprises a casing 27 mounted as for example upon standards 28 on the supply head of the turbine, and provided with an' inner chamber in the lower portion of which are mounted two intermeshing gears 29 and 30 supported onshafts '31 and adapted to be driven in reverse directions by any suitable power means and inany desired manner. The lower portion of the casing is grooved at 32 and provided with a semi-circular chamber struck on an a'rc from the axis of the gear 30, and

the upper part of the casing is divided by a transverse partition 33, which is formed with a concave flaring portion 34 having a curved under face which is struck on an are from the axis of the'upper gear 29. The

partition 33 together with the gears divide the interior of the casing into a pressure chamber 35 and a suction chamber 36. The

chamber 36 communicates with a conduit 37, that extends to the motor casing 23 and communicates with a longitudinal passage 38 therein. This passage through the short by-passages 39, communicates with each of the two end cylinders 20 and 22 at an intermediate oint. The controller casingis provided with two discharge ports 40 and tion with the upper ends of the several other cylinders of the series through passages 45.

The other conduit 43 communicates through a port 46 with the lower end of the c linder 20 and passages 47 serve to establis communication between the lower ends of the several cylinders of the series. Ports 40 and 41 are formed in an extension 48 of the controller casin being separated by a tapering tongue 49, .w ich at itsinner end is brought to a sharp point so thatit forms practically a knife edge division between the two ports where they open into the chamber 35f The purpose of this construction will be a parent :when it is considered that the liqu d, with which the controller casing and the several conduits and cylinders are filled, will be 'forced by the gear, pump into the chamber 35' at relatively high pressure, and from this chamber its only normal outlet is through a movable. nozzle 50, rotatably mounted in the partition-33' and disposed so as to discharge the liquid flowin therethrough into one or the other or oth or said ports 40 and 41 according tov its position relative thereto. The nozzle has a circular head 51 which is mounted in curved seats in the partition, and capable of alimited oscillating movement therein. The nozzle is provided at one end with an operating lever 52 which may beconnected to a governor of any desired construction oroperated by hand. A vided to establish communication between the two chambers in the casing through a passage 54, port 55 and passage 56. The purpose of this shunt passage is to prevent the pressure in chamber 35 from becoming too great. The valve 53 is preferably of the puppet type having a collar 57 disposed in a chamber 58 formed in the controller' casing. I insert a spring 59 in the chamber relief valve 53 is pro- 58 between the collar on the valve and an adjusting screw 60, by means of which the .valve may be adapted to open at any desired pressure. The passage 54 leading from the pressure chamber 35 continues through the casing and communicates with a pressure gage 61 by means of which the pres-.

sure of the liquid in chamber 35 is indicated. To provide for the displacement of liquid by the action of pistons in the several cylinders I provide a reservoir 62suitably supported from the standards 28. A pipe 63 communicating with the conduit 37 enters this reservoir and extends to a point near the bottom thereof.

The operation of the mechanism is as follows: Having introduced the desired quantity of oil, alcohol or any other desired liquid into the motor cylinders and controller casing, and assuming the several valves to be closed, upon starting the rotation of the gears in the direction of the arrows, they will operate in the well known maime- 6 manner as a gear pump to force the liquid under high pressure into the chamber 35. Assuming now that the nozzle is moved to a position opposite the port 40, the liquid flowing through the nozzle under high pressure" will be forced into said port and through the conduit 42 and passages 44 and 45 into the upper ends of the several cylinders tending to hold the pistons down and the valves attached thereto closed. The pressure above the several pistons is created and maintained by the impact of the jet of fluid flowin through the adjustable nozzle 50. Since t e impact effect of the fluid will not take lace the port 41, the suction effect of t e pump will practically draw ofl fluid from below the pistons causing them to be -held in their owered positlon by a pressure substantially equivalent to that indicated by the age 61. As the controller nozzle is loweref the impact effect of the jet of fluid in the port 40 is decreased and that in the port 41 increased until the effective pressure above the head 64 of the piston in cylinder 22 becomes .inferior to the pressure existing below the head 65 of said piston, when the latter will move to the position shown in the drawings and open a supply nozzle. The other pistons, however, will remain in their lowered position until the gradually increasing pressure below them will cause t em to move upward. It will be clear that any desired number of pistons may be controlled in this successive manner. All leakage between the differential heads of the compound pistons is drawn oil through the by-passages 39 and conduit 37, so that it is unnecessary to have the pis- .tons fit pressure tight in their cylinders.

The effect upon the total volume of controller fluid due to the displacement of the differential pistons in their diflerent operating positions, is compensated by the reservoir 62 which receives the surplus liquid or gives'the same back into circulation as occasion may require.

It will be evident that the use of an incompressible fluid to actuate the several controller pistons will give a more direct and positive action than where steam or other elastic fluid is used. And further, there will be no loss by reason of condensation, nor will there be danger of the motors sticking. In fact the small power required to actuate the gear pump and the absence of any loss or waste in the actuating fluid makes this apparatus much more eflicient and economical than those in which steam or other elastic fluid is utilized.

I The motor cylinders and pistons may be designed to produce any desired valve action, and, while designed for use with hydraulic pressure obviously, in-so-far as certain features of my invention are conbe used. Also there maybe as many groups of valves as may be desired.

The operating mechanism for the resilient valves 6 will move the latter toward a closed to increase the power of the fluid motor to hold the valves againsttheir seats over the admission ends -of the nozzles. This permits of the use of smaller fluid motors and hence less power is required of the gear pump. The com ression exerted on' the valves when seat causes them to yield sufficiently to insure a polishing of t eir seats and to prevent leakage. The combined action of the toggle res and resilient valve will be to reduce t e tendency of the valve to hammer its seat and will also reduce the wear and strain on the toggle joints and lever bearings.

' In accordance with the provisions of the patent statutes, I have described the principle of m invention, together with the apparatus w ich I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means.

What I claim as new and desire'to secure by Letters Patent of the United States, is, 1. In a governing mechanism for turbines, the combination of a pluralit of pistons operatively connected to tur ine valves,

serially connected cylinders therefor, means to conduct fluid under pressure from a controller chamber to both ends of said cylinders, and a controller nozzle for said fluid .pressure cooperating with said means and acting to vary thepressure in said cylinders.

2. In a governing mechanism for turbines,

the combination of a plurality of pistons ,operatively connected to turbine valves, cylinders for said pistons, conduits serially connecting the corresponding ends of said cylinders, and a fluid pressure controller means which re ulates the pressure in both ends of said cyhnd'ers and thereby controls the movements of the pistons therein.

3. In a governing mechanism for turbines, the combination of a plurality of pistons operatively connected to turbine valves,

cylinders for said pistons whichare serially connected at their corresponding ends by passages, and a fluid pressure cont-roller mechanism which raises the pressure in one end of the cylinders through one series of passages while it lowers the pressure in the opposite end 'of the cylinders through the other series of passages. v

4. In a turbine, the combination of a nozzle acting to direct fluid pressure against a bucket carrying element, a valve for said nozzle, a fluid actuated motor for said valve,

said jet may and a controller mechanism utilizing aliquid under pressure to operate said motor which a controller, nozcomprisesa force, pump,

said liquid under operating turbine valves that communicate part-ments, a gear pump to comprising a l 6. In a liquidpressure governing with said conduit or conduits. I

mechanism for turbine valves, the combination of a controller chamber dividedv into comforce the liquid fro-m one compartment into the other, a nozzle to discharge a jet of liquid under pressure into one or more conduits through which the fluid pressure acts to .move the turbine valves, and means to return the liquid to said controller chamber.

7. In a governing mechanism utilizing hydraulic pressure, the combination of a plurality of compound cylinders, differential pistons therein operatively connected to valves, ports for admitting fluid under pressure to both ends of said cylinders, means to control and vary the pressure of the fluid admitted through said ports, and a third set of ports through which the liquid leaking past the piston is returned to the main body of fluid. v

I 8. In a governing mechanism for turbines, a plurality of valves, motors for operating said valves, mitting motion from vsaid motors to said valves,-two or more of said elevers being mounted on a common axis.

9. A governing mechanism for turbines comprising standards carried by the turbine, turbine valves, and a plurality of devices"; for transmitting motion from said motors to said valves which are pivotally supported by said standards.

10., A governing mechanism for turbines of intermesh ing gears serving as a pump therein, a partition which, with said gears, divides the interior of the easing into two chambers, a device to control the flow of.

- fluid from the chamber into which it is forced by said pump, a relief valve to establ1sh communication between said chambers,

, and conduits to conduct the fluid pressure charge fluid and toggle levers trans-I supply motors supported by ,said standards,

nected to the turbine, a piston fluid containing casing, a pair' under the control of said device to operate turbine valves.

'11. In an operating mechanism for a turbine valve, a motor frame connected to the turbine, leverage devices journaled in said frame, a motor swivelly onnected to said leverage devices, and means to operate said valve through the instrumentality of said leverage devices.

12. In an elastic fluid turbine, the combination of a nozzle passage adapted to diselement, a resilient cup shaped valve adapted to seat over the admission part of said nozzle passage, and toggle means to operate said valve with only full open and closed positions.

13. In an elastic fluid turbine, the combination of a nozzle passage adapted to discharge fluid pressure against a rotatable element,'a resilient valve therefor, an actuator, and power transmission means between said actuator and valve which retards the move-- supported by said frame and.

pressure against a rotatable ment of the latter as it seats and, increases the power of the former toforce the valve against its seat.- a 1 1 1. In an elastic fluid turbine, the combination of a steam chest, a nozzle passage leading therefrom and adapted to discharge motive fluid. into the turbine, a valve in the form of an inverted resilient cup adapted to seat over the admission end of said nozzle, a stem for said valve which passes through an opening in said steam chest, and a fluid motor mounted on the'turbine and connected to said valve, substantially as described.

15. Inan elastic fluid turbine, the combination of a supply head therefor, a steam chamber in said head, a nozzle passage leading therefrom into the turbine, a resilient valve adapted to seat over the nozzle entrance, a' fluid actuated motor contherein which reciprocates in line with the movements of said valve, and leverage connections between said piston and valve, whereby the latter is given a variable speed of movement and is placed under powerful compression when seated. e 1

In witness whereof, I have hereunto set my hand this 10th day of October, 1911.

JAMES WILKINSON.

Witnesses:

BENIJAMIN B. HULL, HELEN ORFORD.

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