US1748506A - Hydraulic relay governor - Google Patents

Description

Feb- 25, 1930. R. BIRMANN 1,748,506

HYDRAULIC RELAY GOVERNOR Filed Aug. 6. 1927 4 Sheets-Sheet 1 ATTORNEYS.

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HYDRAULIC RELAY GOVERNOR Filed Aug. 6. 1927 4 Sheets-Sheet 5 Feb. 25, 1930.

R. BIRMANN 1,748,506

HYDRAULIC RELAY GOVERNOR Filed Aug. e. 1927 4 sheets-sheet 4 J7 5U .$2 L

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Patented Feb. 25, 1930 UNITED STATES PATENT OFFICE RUDOLPH BIRMANN, OF TRENTON, NEW JERSEY, ASSIGNOR TO DE LAVAL STEAM TURBINE COMPANY, OF TREN TON, `NEW JERSEY, A

CORPORATION OF NEW JERSEY HYDRAULIC RELAY GOVERNOR Application tiled August 6, 1927. Serial No. 211,092.

One of the objects of my invention is to replace, in any governor valve mechanism, the mechanical connection between thepilot valve and the piston for operating the motive fluid admission or governor valve, by hydraulic means and thereby simplify the construction of the governing mechanism and make the location of the valve-actuating piston independent of the location of the governor itself.

Another object of the invention is to provide a construction that will have the desirable characteristics possessed by an isodromic governor, whereby a regulation may be obtained that gives practically constant speed at any load between no load and full load.

Another object of the invention is to provide a construction whereby a regulation may be maintained that gives a substantially constant volume.

The invention is adapted to any kind of governor, such as a pressure governor, volume governor or speed governor used separately or combined. The latter may be of the mechanical (centrifugal) ty e or the pure hydraulic type which dependls for its operation on variation in fluid pressure with variation in speed. The invention is also applicable to any kind of governor which depends for its operation on variation of fluid ressure with variation of volume. A subsi .iary but important object of the invention 1s to` so construct a governor of the hydraulic type as to overcome the well known practical objections thereto and tosimplify its construction and mode of operation.

The invention is capable of embodiment in many different forms, and I have elected to disclose three of many possible specific embodiments of the invention; one in which the governor is a mechanically operated speed governor; and another in which itis a speed' governor of the hydraulic type; and another in which the governor is intended and adapted to obtain a regulation that gives a substantially constant volume; it being understood, however, that the invention, in its broader aspects, is not dependent for its successful operation on the use of any particular construction of governor.

In the drawings:

lig. 1 is a side view of the governing mechanlsm and the connections therefro'm to the governor .valve and its actuating piston.

Fig. 2 1s a vertical sectional view of the governor proper and of the pilot valve and appurtenant parts embodying my invention.

Fig. 3 is a vertical sectional view of my improved pilot valve and appurtenant parts associated with a dillerent type of governor.

Fig. 4 is a vertical sectional view of my improved pilot valvel and appurtenant parts in which the governor is adapted to act as a constant volume governor.

5 is a section on the line 5-5 of Fig. 4. Flg. 6 is a section onthe line 6 6 of Fig. 4. Referring first to the construction shown in Figs. 1 and 2:

The shaft a may be assumed to be the shaft of a turbine or any other prime mover. Shaft a drives the 'governor shaft c by any known means, such as by spiral gears b. Shaft o carries `a flanged disc d, in which is vertically movable a for supporting a coiled sprin j. Plate f supports, on a ball race, a sha g which, at its upper end, slides in a bearing plate la secured to a casing z' that encloses the parts described. Spring j is confined between plate f and a plate q, the latter being threaded on the end of a ring q' enclosing 'the s ring and rigidly secured (by means not s own) to disc d.

The centrifugal governor comprises two semiyclindrical weights lc, la which are fulcrulned at m, m on the flange of disc d and are adapted to be centrifugally actuated to swing out on their fulcrums.

The stem of the pilot valve 10 may be integral with shaft g, but it is preferable to connect them by a flexible joint n to dispense with the necessity of exact alignment between shaft g and the pilot valve.

spring s is confined between a plate o on the upper end of shaft g and an adjusting nut p threaded in an annular llange r on casing i.

The governor need not be more particularly described, as it is of a well known type and may be replaced by any other operable type of governor. The pilot valve 10, provided stud e carrying a plate fy with the pistons 12 and 13, slides in a sleeve 11 which itself is slidable in a valve casing or valve body t mounted on casing i and has ports communicating With ports 14, 15 and 16 in the valve casing. The intermediate pressure port 15 is open to an oil admission pipe 17. Ports 14 and 16 are respectively connected, by means of pipes 18 and 19, with the top and bottom sides of an operating piston 20, which controls the valve y for admitting pressure fluid to the turbine.

The upper end of the pilot valve sleeve 11 1s provided with a piston 21, which works in a cylinder 22 formed in the upper end of the valve body t. Springs 23,23 are confined between piston 21 and the end walls of cylinder 22. The piston is provided with a restricted orifice 24 to allow slow leakage of oil from one side of the piston to the other.

A passage 140 connects port 14 with the bottom side of piston 21. A passage 160 connects port 16 with the top side of piston 21. Valves 141 anad 161 are interposed in the passages 140 and 160 respectively.

In the usual type of fly ball governor, wherein the governor and governor valve operating piston are connected to opposite end intermediate part of which the pilot valve is connected, a drop in load, with resultant speeding up of the turbine, lifts the governor end of the lever` on the operating iston end of the lever as a fulcrum, therey actuating the pilot valve, which, through the working fluid, actuates the operating piston to cause it to start to close the pressure fluid admission valve, thereby moving down the operating piston end of the lever on the governor end of the lever as a fulcrum and returning the pilot valve to closed position. The result is that the turbine carries a different load and runs at a different speed, with the main valve in a different position but with the pilot valve in the same closed position. If the governor valve would actuate the pilot valve directly without the floating transmitting lever, continuous hunting would result.

In the governing mechanism embodying my invention, the return motion is effected, not b moving the pilot valve 10, but by moving the pilot valve sleeve 11. This in itself is not new, the novelty residing in the way the movement is obtained and co-ordinated with the movement of the operating piston, as will be understood from the following description of the mode of operation.

Assuming that the turbine is running under any load, pilot valve 10 with pistons 12 and 13 will assume a position in relation to sleeve 11 as shown in Figure 2. This relation of parts represents the normal position to which the parts would tend to return after any change in governor action. It will be noted that the preferred arrangement will cause the upper edge of lower piston 12 and s of a floating lever, to anthe lower edge of upper piston 13 to barely clear the ports in sleeve 11, while the upper end of piston 13 and the lower end of piston 12 should overlap with the small amount of the ports in sleeve 11.

Assuming an increase of load, the turbine will tend to slow down and the centrifugally actuated governor Weights will move closer towards the center from the quiescent position shown in full lines in Figure 2 and will assume a new position as shown in dotted lines. Pilot valve 10, following the movement of the governor weights, will assume a lower position, as shown in dotted lines, thereby admitting working fluid (oil) under pressure through port 17, valve sleeve 11 and port 16 to pipe 19 and thence to the bottom side. of operating piston 20, thereby further opening governor valve y. At the same time, oil flows through assage 160, through valve 161 to the top of) piston chamber 22, thereby forcing downwardly piston 21 and sleeve 11 to which the piston is secured.

By proper adjustment of valves 141 and 161 and proportioning of hole 24, the movement of sleeve 11 by springs 23 can be controlled. With the increase of load, therefore, the following movements will take place: the movement of governor weights k towards the center, the downward movement of pilot valve 10 opening port 16, the upward movement of piston 20 and valve y, the downward movement of sleeve 11, and the closing of port 16. Immediately upon the openingof valve y by piston 20, the turbine receives a larger volume of steam and increases its speed, causing governor weights k to assume their normal position, returning the pilot valve to its normal position. At the same time the oil pressure on opposite sides of piston 21 has become the same due to the flow of oil through opening 24, and piston 21 with sleeve 11 has been pushed upward by lower spring 23 returning sleeve 11 to normal position simultaneously with the return of the pilot valve to its normal position by the governor. It will therefore be seen that the action of the governing mechanism caused by the increase in load has caused the governor valve to open to a greater amount without any permanent change in position of governing parts, consequently causing no permanent change in speed resulting in an isodromic action of the governing mechanism.

Assuming a decrease of load, pilot valve 10 will move up, thereby admitting working fluid through pipe 18 to the upper side of operating piston 20, which moves to more or less throttle the governor valve y. At the same time oil flows through passage 140 to the bottom of piston chamber 22, thereby lifting sleeve 11, while the working fluid forced out by the operating piston through line 19 exhausts through grooves in the bottom piston of the operating valve.

-venturi meter.

In another embodiment of-my invention shown in Fig. 3, the pilot valve is operated hydraulically in a manner-,which, inj principle, is old, but by means which my invention permits to be lmuch simplified. The turbine'shaft 30 is provided with an impeller 31 which extends into a channel'32 in the governor and ilot valve 'casing 40, which channel, througIh port 17, communicates with the intermediate port in the .pilot valve sleeve 11, and, through port 33, with a chamber 34 under a piston 35 on the stem ofthe pilot valve 10. The stem ofthe pilot valve carries a lhead 36, which A'operates against a spring 37 confined against a head 38 adjustable by a'ha'nd screw 39'in the casing-l0. It will be understood that with decreaseofload, the shaft speeds up, increasingthe fluid pressure in the .channel32 vand lifting-the pilot valve; While lwith 'increaseot load, shaft 30 slows down, decreasing t-he fluid pressure in thechannel y spring 37 to move the pilot valve down. The operation of the pilotl valve is the same as when operated by a mechanical governor and the -same isodromic operation is obtained.

In another embodiment of the invention shown in Fig. 4, the movementof the pilot valve is controlledby a ldiaphragm .which 1sV subjected to a difiere vtial pressure that is' obtained by connectingl opposite sidesv of. the diaphragm with the mouth,v and throat of vva In-.the drawings the dia-A phragm 50, enclosed in a casing 51,l is arranged to operate the stem of the pilot valve '10. Pipes 52 and 53, extending fromthe spaces within the casing on opposite sides of the diaphragm, are connected with a venturi meter not shown). p The valve stem 10l comprises upperandlower' sections secured'to a frame 60, which is supported from flexible arms 61 carried on the twoarms of a yoke 62. A lever 63 secured at one end to a flexible support 641 extends between the ends ofthe two sections of valvestem 10, and has secured to its op osite end 'a spring 65. The

construction of t e pilot'valve, the valve sleeve v and its fluid-actuating means, andthe valve casing and the arrangement'of the ports and passa es, may be the same as in Figs. 2 and 3, an the operation is the same as when o perated by a mechanical governor, as in Fig.,- 2, or hydraulically, as in Fig. 3. The exhaust normally close-communication between said of working fluid from the operating-piston escapes into the pilot valve casing and outflows through the drain 55. The only"v differencein the operation of the apparatus, as a whole, is that the motion of the pilot valve is controlled -by the deflection ofthe diaphragm, which deflection is in accordance with the change in volume of fluid passing through the venturi meter; the governor therefore acting as a constant volume gover-l nor.v

The three embodiments of my invention v'possible applications-of the invention.

but the power piston 32 and allowing'the working vbination with a drivingelement shown are merely illustrative of numerus ot only may the pilot valve be actuated by a speed governor, or by a pressure governor, or by a ldiaphragm subjected to change in pressure or temperature, or lby other means, may be adapted to any classof service. It may, for'vexamp'le, control, instead of ical element such as the'grate of a `'StokerV or the stem of a valve.

Having now fully-described 'my invention,

what I claim and desire topprotect vby Let-f ters Patent is 1. In a governor for a machine, the-,com-

driving element of the ma bination with Va chine and a device controllingr the operation of the machine, of fluid-controlled-means to actuutesaid device, apilot valve casing, pilot valve mechanism comprising a l free-'floating valve sleeve `movable relatively one to another and both mechanically independent of said actuating means for said controlling device, `fluid-actuated means adapted t0 operate the valve sleeve, and means controlled from said driving element vto actuate the pilot valve, said casing being provided with a working fluid pressure port and channels for passage the'actuating means for said controllingdevice and to the pilot valve sleeve actuating means, said pilot valve mechanism being provided with .ports controlling the passage of fluid from said pressure port throughsaid channels, the pilot valve being vactuable toA open communication from said pressure port to cause working fluid to operate the actuating means for said controlling device and also to operate the pilot valve sleeve actuating means to move -the .pilot valve sleeve toward a position tov close said communication.

2. In a governor fora machine, the comof -the` machine and a device controlling the operation of the machine, of a piston for actuating said device, a pilot valve casing provided with a ort for inflow of working fluid and two ports for outflow of working fluid, a movable ilot valve sleeve provided with three ports a apted to register with therespec-tive ports in the valve casing, a pilot valvelcomprising pistons working in .said sleeve and adapted to inflow port and both outflow ports but adapted to be moved into position to open com-A munication between said inflow port and either outflow port, said pilot valve and sleeve being mechanically independent of the first mentioned piston, means operable vfrom said valve and a" a prime mover, any mechanof working fluid to ing piston and between said outflow ports and opposite sides respectively of the valve sleeve piston, whereby .the actuation of the pilot valve to open the inflow port to an outflow port causes the working fluid to actuate said actuating piston and the sleeve piston and moves the latter toward a position tending to close communication between the inflow port and such outflow port.

In a governor for a machine, the combination with a driving element of a machine and a device controllingr the operation of the machine, a fluid-controlled means to actuate said device, a pilot valve casing, pilot valve mechanism comprising a valve and valve sleeve movable relatively one to another and both mechanically independent of said actuating means for said controlling device, fluid-actuatedineans adapted to operate the valve sleeve, means controlled from said driving element to actuate the pilot valve, said casing being provided with a working fluid pressure ort and channels for passage of working uid to the actuating means for said controlling device and to the pilot valve sleeve actuating means, said pilot valve mechanism being provided with ports controlling the passage of working fluid from said pressure port through said channels and being normally'in a median position closing communication between the pressure port and said channelsthe pilot valve .bein actuable to open communication from-sai pressure port to cause working fluid to operate the actuating means for said controlling device and also to operate the pilot valve sleeve actuating means to move the pilot valve sleeve toward aposition to close said communication, and spring mechanism tending to restore the pilot valve sleeve to a median position, thereby necessitating the 'restoration of the pilot valve to the said normal position occupied in order to maintain closed communication between the pressure port and said channelsf l 4. In a governor for a machine, the combination with a driving element of the ma chine and a device controlling the operation of the machine, of fluid-controlled means to actuate said device, a pilot valve casing, pilot `valve mechanism comprising a valve and v alve sleeve movable relatively one to another and both mechanically independent of said actuating means for said controlling device, a fluid-actuated piston adapted to operate the valve sleeve, means controlled from said driving element to actuate the pilot valve, said casing being provided with a working fluid pressure port and channels for passage of working fluid to the actuating means for said controlling device and to the pilot valve sleeve actuating meanswhereby` each of said rif-leans is operable by said working fluid, said pilot valve mechanism being provided with tuating means,

ports controlling the passage of working fluid from said pressure port through said channels and being normally in a median position closing communication between the pressure port and saidlchannels, there being a restricted orifice affording communication between opposite sides of the sleeve piston, and spring mechanism tending to restore the pilot valve sleeve to a median position.

5. In a governor for a machine, the combination with a driving element of the machine and a device controlling the operation of the mach-ine, of fluid-controlled means to actuate said device, a pilot valve casing, pilot valve mechanism comprising a valve and valve sleeve movable relatively one to another and both mechanically independent of said actuating means for said controlling devices, fluid-actuated means adapted to operate the valve sleeve, a working fluid pressure port channels, for flow of working fluid to the actuating means for said controlling device and the pilot valve sleeve actuating means, said pilot valve mechanism being provided with ports controlling the flow of working fluid from said pressure port through said channels, a pressure fluid conduit communicating with said pressure port, means operable by said driving element to control the fluid pressure in said conduit, means controlled by said fluid pressure to actuate the pilot valve, the pilot valve being actuable to open communication from said pressure port to cause working fluid to operate the actuating means for said controlling device and .also to operate the pilot valve sleeve actuating means to move the pilot valve sleevetoward a position to close said communication.

6. In a governor for prime movers, the combination of the driving shat, a governor valve controlling admission of actuating fluid to the prime mover, fluid-controlled means to actuate the governor valve, a pilot valve casing, pilot valve mechanism comprising a valve and valve sleeve movable relatively one to another and mechanically independent of said fluid controlling means for actuating the governor valve, fluid-actuated means adapted to operate the valve sleeve, and means controlled from said shaft in accordance with its speed to actuate the pilot valve, said casing being provided with a working fluid pressure port and channels for passage of working fluid to the governor valve actuating means and the pilot valve sleeve acsaid pilot valve mechanism being provided with ports controlling the pgassage of working fluid from said pressure 1 port through said channels, the pilot valve being actuated, upon change of load, to open communication from said pressure port to cause working fluid to operate the governor valve actuating means and also to operate I RUDOLPH BIRMANN.

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