US770995A - Governing mechanism for turbines. - Google Patents

Description

No. 770,995. PATENTED SEPT. 27, 1904. J. WILKINSON.

GOVERNING MECHANISM FOR TURBINES.

APPLICATION FILED JULY 23, 1904.

N0 MODEL, 2 SHEETS-SHEET 1.

1 *3 t 11 I N 0Q MN Q ggg %%g I K T'T 5 i 2 if x j g ii-:17 N U r N WITNESSES: I I [N VEN TOR. James 144%760/7 No. 770,995. Y PATENTED SEPT. 27, 1904. J. WILKINSON.

GOVERNING MECHANISM FOR TURBINES. APPLICATION FILED JULY 23, 1904. 7 N0 MODEL. I gyms-sum 2.,

UNITED STATES Patented September 2'7, 1904.

' PATENT OFFICE.

JAMES WILKINSON, OF BIRMINGHAM, ALABAMA, ASSIGNOR TO THE WILKINSON STEAM TURBINE COMPANY, OF BIRMINGHAM, ALA- BAMA, A CORPORATION OF ALABAMA.

GOVERNING MECHANISM FOR TURBINES.

SPECIFICATION forming part of Letters Patent No. 770,995, dated September 27', 1904.

I Application filed July 23, 1904:. Serial No. 217,820. No model) To (all whom it may concern.-

Be it known that I, JAMES WILKINSON, a citizen of the United States, residing at Birmingham, in the county of J eiferson and State of Alabama, have invented new and useful Improvements in Governing Mechanism for Turbines, of which the following is a specification.

My present invention relates to a governing mechanism for turbines having as its object to distribute the wear equally upon the turbinevalves and to effect a control of the supply of motor fluid, so that its volume varies in direct correspondence with the load on the turbine.

Heretofore I have shown and described in patents issued to me various controller devices for turbine -valves, the operation of which has been to successively open the valves as the load increases, intermediate-load conditions between points of regulation represented by the horse-power capacity of each nozzle being compensated by slowly pulsating the valve at the critical point of regulation to produce intermittent blasts of pressure whose mean potential was proportioned to the intermediate load condition. herethe load on the turbine is generally a constant one and also where, though varying, .it remains above a given load, it must be evident that certain of the turbine-valves will he rarely operated, while the major part of the wear and tear will fall upon the same valve or valves. This is undesirable, since more satisfactory results will be obtained when all the valves are exercised equally. WVith this end in view I have conceived that when all the valves are continually operated in succession by a controller device which varies the number of them maintained open simultaneously in proportion to the load the most satisfactory results will be obtained. In the accompanying drawings I have illustrated a controller mechanism designed to carry this method of valve control into effect-in connection with a plurality of turbine-valves operated singly or in groups by fluid-pressure under the control of a plurality of secondary valves. A governorshift-ed rotating device provided with a tapering controller portion successively operates each of the secondary valves in turn, maintaining a certain number of them open according to the load and continually changing the identity of the open valves as the device rotates. The secondary valves are so arranged and the controller device so proportioned that under a constant load requiring a volume of motor-fluid pressure equal to that supplied by a given number of nozzles the controller device will continually actuate the same number of secondary valves which control the required number of nozzles; but when the load requires an increase or diminution of the fluidsupply less than the capacity of one nozzle the controller device compensates these intermediate points in regulation by intermittently including a greater or less number of secondary valves in those continually maintained in operation and corresponding to the nearest point of regulation. By this means I secure, in effect, a combined constant and intermittent supply of motor fluid and can keep the fluid- 1 supply directly proportioned to the load without any uncertain or Wiredrawing action of the valves.

My invention further comprises the details of construction and arrangement of parts hereinafter described, and more particularly pointed out in the claims, reference being had to the accompanying drawings, forming a part hereof, and in which Figure 1 is a side elevation of a five-stage reversible turbine embodying my present invention and adapted to actuate a rope drive sheave or pulley. Fig. 2 is avertical sectional view through the fluid-controller chamber along the line 1 3/ of Fig. 4:. Fig. 3 illustrates a valve-actuating mechanism for a reversing-turbine with a reversing-valve and its chamber shown in cross-section. Fig. 4 is an end view of the governing mechanism, showing the conduits for the valve-actuating fluid leading to the valve-motors. Fig. 5 is a view along the line in m, Fig. 2. Fig. 6 is a detail view of the rotating controller-piston. Fig. 7 is a view showlng the casing for the reversing-valve mounted upon the supplyhead. Fig. 8 is a detail View of the reversing-valve.

Similar reference -numerals refer to the same parts throughout.

1 have illustrated my invention as applied to a multiple-stage reversing impact-turbine mounted on a bed-plate 1 and acting to drive a rope sheave or pulley 2 by means of a main shaft 3, suitably supported in bearings 4:, which are also bolted to the bed-plate. The turbine comprises an outer shell 5, which surrounds the inner casing formed by the supply-head 6, and any suitable number of peripherally-flanged diaphragm-partitions interposed between said supply-head and the exhaust or condenser casing7, the exhaust-opening from which is disposed downwardly between the side frames of the bed-plate. Motor-fluid pressure is admitted through a port 8 into an annular chamber formed between the shell 5 and the turbine-casing and through transverse passages 9, leading inwardly through the supply-head. This pressure is admitted from the annular chamber to the for ward or reverse nozzles 10 and 11, respectively, which discharge it under the control of valves 12 and 13 against buckets let and 15, respectively. Each transverse passage 9 is provided with ports 16 and 17, the former of which admits motor fluid to a cylinder 18, within which moves a piston 19, suitably connected to a valve 12, and the latter of which admits pressure to a similar cylinder 20, within which is disposed a piston 21, connected to a valve 13. (Shown in Fig. 3 in a closed position.) A coil-spring 22 is disposed in a recess in each of the head-blocks 23 of the cylinders 18 and 20 and engages thepistons 19 and 21, tending to move them toward their closed position. Suitable apertures in the pistons 19 and 21 permit a graduated flow of the pressure from the high to the low pressure side of the pistons. The valves 12 and 13 are preferably of the rotary type shown and describedin my Letters Patent N 0. 752,496. The diaphragm-partitions and subsequent valvemotors and valves correspond to those described in the supply-head, being analogous in their construction and arrangement of the disclosure in the patent aforesaid. The fluidpressure admitted by either nozzle 10 or 11 flows through a working passage of increas ing proportions and acts to drive the turbine in one or the other direction. The turbine, according to its capacity, may have any desired number of nozzles 10 and 11, which may be arranged in parallel rows extending partly or wholly around the turbine. The construc tion and arrangement of valves and their motors hereinbefore described while considered preferable does not constitute an essential part of the present invention, which relates particularly to a valve-controlling mechanism and can readily be adapted to control the valves and regulate the supply of motor fluid to any of the various types of turbines shown and de scribed in the several Letters Patent which have been granted me.

My present governing mechanism comprises a controller casing or cylinder 24, connected to the supply-head and communicating with the boiler-pressure through a passage 25, leading upwardly through the casing to a cylinder 26, in which is disposed a rotary valve 27, which controls the admission of the pressure to the passage 28, leading to the top of the cylinder. A controller cam-piston 29 is vertically momble in the cylinder, being provided with a suitable packing-ring 30 around its upper cylindrical head, which prevents the escape of pressure around it from the upper end of the cylinder. This piston is shifted and also rotated by a stem 31, leading through the cylinder-head 32, where a packing-gland 33 prevents a leakage of pressure from the cylinder around the stem. The upper portion of the stem is squared at 34 and passes through a pinion-wheel 35, which is rotatably journaled in a standard 36, mounted on the cylinder-head 32. This standard is bent at right angles and forms at its forward end a sleeve, within which the cylindrical journal 37, integral with the wheel 35, rotates. A nut 38 engages the top of this journal 37, and a washer 39 is disposed between the nut and the top of the sleeve. In this manner the pinion is free to rotate in the standard, but is held against other movement, while the stem 34, though adopted to rotate with the pinion 35, is at the same time capable of adjustment relative thereto, since its squared end can slip back and forth freely through a square opening in the journal 37. A worm-shaft 40, driven by suitable gear means from the main shaft 3, is journaled at its upper end in two arms 41, formed integral with the standard. The detachable worm-gear 4E2, mounted on shaft 10 and disposed between arms 41. meshes with the pinion 35, causing it to rotate when the turbine is in motion, the proportion between the gear and worm being that most suitable for the successful controlling operation of the piston. The cylinder 24: at its bottom communicates with an exhaust or condenser pressure through a passage 43, and a restricted passage 441 leads longitudinally through the piston 29 andpermits a limited outflow of the high pressure above the piston to maintain enough circulation to prevent the accumulation of water of condensation above the piston and to cooperate with valve 27 in regulating the pressure above the piston, which determines its operating position. At an intermediate point in the side of the cylinder-casing I provide a plurality of outwardly-disposed integral projections &5, each of which is provided with an internal valve-chamber 4E6, beveled at its inner end, where it opens into the main cylinder. At their outer ends the valvecylinders are screw-threaded for the reception of the threaded ends of pipes 47, which lead to the valve-motors in the manner hereinafter described. I provide a valve 48 in each cylinder 46, which is beveled at its forward end and ing to maintain it in its closed position against its beveled seat. This same construction applies to the several valve-cylinders 46, and it will be noted in Fig. 5 that the inner'beveled ends of the valves 48 project inwardly into the cylinder 24 when the valves are seated. To enable one or more of the valves, therefore, to be positively seated, I have provided the piston 29 with a reduced portion 50 in the form of an inverted frustum of a cone with its base taken on a transverse plane through the piston at an angle to its flattened top portion. This angularly-disposed plane through the piston, from which point the downward tapering of its circumference commences, begins at a point a short distance from the bottom and extends to a point adjacentto the packing-ring 30. The vertical movement of the piston 29 in its cylinder 24 corresponds in extent with the conical portion 50, the arrangement being such that when the piston is moved in the manner now to be described to the top of the cylinder all of the valves 48 will be closed by reason of the fact that the tapered portion of 50 will be opposite all of them,and their beveled ends not engaging anything within the cylinder will be seated by the action of the springs 49 and whatever pressure there may be in the pipe 47. On the other hand, when the piston 29 is lowered its full stroke the cylindrical portion 29 will be opposite all of the valves 28, and they will all be held in their open position, when pressure will be exhausted from all of the pipes 47, due to the fact that a clearance is provided between the lower portion of the piston and its cylinder, by which means the pressure escapes to the bottom of the cylinder and thence through passage 43 to the exhaust. The packing-ring 3O prevents the high pressure above the piston escaping around it to the exhaust or acting to open valves 48. Since the several controller-valves are disposed equidistant about the cylinder 24 for intermediate operating positions of the piston, its tapering portion will move opposite to each of them successively, actuating it once during each revolution of the piston. The length of time during which the cylindrical portion of the piston remains in engagement with each of the valves determines the duration of the valves open periods, and since the tapering character of the reduced portion 50 causes the cylindrical portion to increase gradually from a point to a complete circle it follows that the relative position of the pisneously open.

ton and valves controls not only the time during which each valve is held open, but also the number of valves which are held simulta- By reference to Fig. 5 it will be seen that the piston will maintain a group of four valves always open and will add a fifth valve to the group of open valves periodically. As shown, the valves A, B, U, and H are held open, while the valve G is on the point of closing. The latter valve will close before the valve D is open, and during the time that the valves A to D, inclusive, are open the valve H will be open for ashort period. The controller-piston thus maintains a group of four valves of changing identity always open and at the same time will secure the effect of the pulsatory control of one valve by maintaining five valves open at regular intervals. The length of the period during which this extra valve will be open also depends upon the operating position of the piston. Thus if the piston be lowered from its position in Fig. 5, the period during which five valves will be open will increase until as the piston lowers five will always be maintained open. This latter position of the piston represents a point in the control where the capacity of the nozzles controlled by the open valves corresponds with the load on the turbine. If the load continues to increase, it will become greater than the latter nozzles can handle, but less than a load requiring the full supply of the nozzles controlled by six valves 48. To compensate this intermediate load condition, a sixth valve will be added to the open group for intervals of increasing duration until. six valves are maintained open. Thus as the load increases to full load an increasing number of valves will be maintained open for lengthening periods until all the valves are maintained always open. As the load falls a reverse action takes place, the valves being successively opened in diminishing numbers and for relatively decreasing periods of time until all are held closed. Under a constant load each of the valves will be successively opened at regular intervals of time, the speed of rotation of the controller-piston being preferably so reduced that it will open the valves as slowly as one each second. The exercising of each valve, which operates without intermediate positions, prevents its becoming stuck from lack of use and preserves the surface of its seat. It is my purpose to control the operating position of the piston 29 in this cylinder by means of a speed-governor 51, which operates a pivoted arm 52, mounted on the upper portion of the end bearing 53 for the shaft. The arm 52 engages a rod 54, which in turn is pivoted to a crank 55, connected to the stem of the rotary valve 27, which controls the admission of pressure through the passage 28 to the upper portion of the cylinder 24. As the governor moves sensitive to the speed of.

shaft rotation, it moves the valve 27 to admit more or less pressure against the top of piston 29, which tends to move it downwardly,

while the pressure escapes slowly through passage 21- to the lower cylinder, whence it exhausts through passage e3. To oppose the downward tendency of the pressure above the piston 29, I admit the boiler-pressure to a cylindrical recess in the bottom portion of the piston through a passage 56, communicating with boiler- 'n'essure in the passage 25. This passage 56 leads through a cylindrical guide 57, integral with the bottom portion of the cylinder 24 and extending into the recess in the piston and centering it in the cylinder. Vithin the recess in this guide is disposed a coil-spring 58, which engages a circular plate 59, provided on its other side with an annular groove corresponding with a similar groove in the end portion of the recess in the head. These grooves form a raceway for a plurality of antifriction-balls 60 to reduce the friction between the rotating piston 29 and the plate 59, through which the pressure of the spring is made effective against the piston. The spring serves the purpose of positively actuating the piston against the action of the pressure under the control of the valve 27 and secures a positive operating position for the piston corresponding to the governor-shifted position of the valve 27. In this manner the variable spring-pressure and the constant boiler-pressure below the piston act in conjunction with the governor-controlled pressure above it to hold it in definite stationary operating positions, which correspond to definite positions of the valve 27.

Having thus described the manner in which the pressure may be maintained or exhausted from the several pipes 17 by the controller action of the piston 29, I will now describe the manner in which this piston controls the operation of the turbine-valves 12 and 13, it being understood that each of the passages 5L7 may be adapted to control a plurality of valves 12 or 13 either around the head or across the stages and that there may be as many of these valves arranged around the turbine as desired.

In Figs. 3 and 4 I show branch passages from each passage 65, which lead through the casing to a row of valves (not here shown) disposed across the stages in the line of the fluids flow. In the same manner branch passages 66 lead from passages 66, the stagevalves being controlled as is more fully described in my Patent No. 752 196. In Fig. 4. I illustrate a plurality of motors for a plurality of supply-valves 12.

The several pipes 47 communicate with a multiple valve-cylinder 61, formed in the easing 62, mounted upon the supply-head 6 above a group of supply-valves 12 and 13. A compound rotary valve 63 is mounted in the cylinder 61 and provided at points opposite each pair of valves 12 and 13 with ports formed motor-cylinder 20.

by cutting away or grooving out opposite sides of the valve and leaving a narrow intermediate web portion 6 1. Passages 65 lead from one side of the cylinder 61 to each motor-cylinder 18, and similar passages 66 lead from the opposite side of the cylinder to each A passage 67, communieating with a source of high pressure, preferably that of the motor fluid, leads longitudinall y through the casing 62 below the valvecylinder 61 and by means of suitable by-passages admits boiler-pressure into the casing at points opposite the reduced. portions of the valve 63. Thus, as seen in Fig. 3, when the valve 63 is moved to one of its operating positions pressure from the passage 67 will pass through the cylinder 61 and all of the passages 66 and entering the upper end of cylinders 20 will close all of the valves 13, which admit pressure to the reversing working passages. At the same time the upper ends of the cylinders 18, through passages 65, will be in direct communication with the pipes 17 through the valve-cylinders 63. When the piston 29 unseats a valve 18,the pressure from the upper end of the cylinder controlled by said valve will be exhausted through the pipes 17 and 43, when the pressure existing below the piston 19 will raise it and move the valve 12, controlled thereby, to its open position, thus admitting motor fluid to the outer or forward driving working passage. It follows, therefore, that when all of the valves 48 are unseated all of the pistons 19 will be raised and a full supply of motor fluid will enter the forward driving working passage, and, conversely, when all of the valves 48 are seated the pressure below the pistons 19 will flow through the restricted apertures in the pistons and accumulate in the pipes 47. I/Vhen the pressure above and below the pistons is balanced, the springs 22 will move the pistons downwardly and close all of the outer row of valves. This same action takes place. in connection with the valves 13 when the valves 63 are moved, so that the passages 66 are in communication with the passages 17 and the passages 65 are in communication with the boiler-pressure in passage 67. The valve 63 is provided with a stem 68, which projects through the shell 5 and has attached thereto a handle 69, by means of which the turbine is reversed, the fluid-pressure acting through passages 65 and 66 to close all the stagevalves of a working passage when the supplyvalves are closed.

My present controller mechanism in effect secures a similar valve action to that described in my several Letters "Patent numbered 751,888, 7et1,426, 752,610, 753,772, and 753,773, and though described herein in connection with a fluid-pressure mechanism for,

operating the valves I do not desire to limit myself thereto. This method of controlling the operation of turbine-valves may be adapted in an obvious manner to actuate the valves directly or to utilize electricityorliquid-pressure as a means to operate them, or a controller nozzle or nozzles such as are described in my last-mentioned patent above may be shifted to produce the same eifect.

It is my intention to protect, broadly, the novel idea of successively and periodically actuating all of a group of turbine-valves, varying the number of them held simultaneously open in proportion to the load.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. A governing means for amultiple-nozzle turbine comprising a controller device, means acted upon by said device periodically to open the nozzles under its control When the turbine is operating under a fraction of its full load, and governor means to vary the period during which each nozzle is open in accordance with the load.

2. In a governing mechanism for turbines, a plurality of motor-fluid valves, and a controller mechanism therefor which exercises all said valves equally by opening them successively for periods which vary with the load.

3. In a governing mechanism for turbines, a plurality of motor-fluid valves, a controller device which, under a fractional load, successively opens and closes said valves, and a governor means to shift said device to vary its controlling effect on said periodically-operated valves.

4i. In a governing mechanism for turbines, a plurality of motor-fluid valves and a controller mechanism for said valves which periodically actuates all of said valves, varying the number held simultaneously open in accordance with the load.

5. In a governing mechanism for a turbine having a plurality of fluid-pressure nozzles, means to open and close said nozzles, and a rotating controller mechanism which successively opens all of said nozzles, simultaneously holding a varying number of them open in accordance with the load.

6. In agoverning mechanism for a turbine having a plurality of motor-fluid valves, a plurality of independent means to actuate said valves singly or in groups, a controller mechanism acting upon said actuating means and adapted to successively energize all of them and to vary the period during Which each of said means is energized in accordance With the load.

7. In a governing mechanism for an elasticfluid motor, a plurality of motor-fluid valves,

8. In a governing mechanism for an elasticfluid motor, a plurality of motor-fluid valves, a plurality of independent means to control the operation of said valves, means to successively operate each of said valve-actuating means to cause the valves under its control to open for varying periods of duration, and means to vary the said periods of duration in accordance with the load.

9. In a governing mechanism for a fluidmotor having a plurality of independent valves, a plurality of means to control the operation of said valves singly or in groups, a controller mechanism which acts upon said controller means to exercise all of said valves periodically while maintaining varying numbers of them simultaneously open.

10. In a governing mechanism for an elasticfiuid motor having a plurality of motor-fluid nozzles, a controller mechanism for said nozzles comprising a plurality of means to open and close them, and a rotating device having a tapering controller-surface adapted, during intermediate load conditions, to successively energize each of said means, maintaining always open a group of nozzles of continuallychanging identity whose combined capacity is proportioned to the load.

11. In a governing mechanism for an elasticfiuid motor having a plurality of motor-fluid nozzles, a controller mechanism for said nozzles comprising a plurality of means to actuate said valves and a rotating device having a tapering controller-surface adapted, during intermediate load conditions, to successively energize each of said means, maintaining always open a group of nozzles of changing identity, Whose combined capacity is approximately proportioned to the load and adding an additional nozzle or nozzles intermittently to the open group to compensate fractional variations in the load between points of regulation when another nozzle or group of nozzles. will be added or Withdrawn from the normally open group.

12. In a turbine, a pluralityof independent nozzle-passages, independent means to open and close said nozzles, and a tapering controller device which successively engages said means under fractional loads to periodically open and close the nozzles, and which is adapted under increasing loads to increase the number of nozzles held simultaneously open and the length of the open periods of each nozzle until under a full load all the nozzles are maintained open.

13. In a multiple-nozzle turbine, valves to control the flow of motor fluid through the nozzles, and a controller mechanism comprising a plurality of secondary valves controlling a relay power to operate said turbine-valves, and a moving governor-shifted device adapted under all fractional load conditions to periodically operate each of said secondary valves and maintain more or less of the turbine-nozzles under their control simultaneously open according to the load.

14. In a governing mechanism for a fluid motor, a plurality of fluid-actuated motorvalves, a plurality of secondary valves controlling the operation of said n1otor-valves, a controller device having a cam-surfacc, said secondary valves being disposed around said device and adapted to be successively actuated by its cam-surface, and means to rotate and shift said controller device.

15. In a governing mechanism for a turbine, a plurality of turbine-valves, a rotating camcontroller device and means for actuating said valves disposed at regular intervals around said device and successively engaged thereby, whereby it effects the successive operation of said turbine-valves, and a governor means to adjust the relative position of said device and said valve-actuating means.

16. In combination with a turbine having a plurality of motor-fluid valves, means to control the operation of said valves comprising a cam-controller device, means actuated by said cam device to operate said turbine-valves, means to rotate said device and means to shift its position relative to said valve-actuating means which are disposed around it and adapted to be successively actuated by it when the turbine is operating under fractions of its full load.

17. In a governing mechanism for a multiple-valve turbine, a governor-shifted controller device in the form of a cylinder having a tapered portion disposed to one side of the line of intersection of an oblique plane passing through said cylinder at an intermediate point, and means actuated by said device to operate said turbine-valves.

18. In a governing mechanism for a multiple-nozzle turbine, a plurality of independent means to control the flow of fluid through independent nozzles, and a controller device to actuate said means comprising a tapering controller-surface around which said means are disposed, and means to shift and rotate said controller device.

19. In a governing mechanism for a multiple-valve turbine, a fluid-pressure means to actuate said valves, independent secondary valves controlling the operation of said turbine -valves, a controller cylinder around which said secondary valves are disposed and within which they normally project, and a tapering controller-piston rotatably and ad- ,justably mounted in said cylinder and adapted to successively actuate all of said secondary valves during fractional loads on the turbine, opening them for intervals in proportion to the load.

20. A controller mechanism for a multiplevalve turbine comprising a controller-casing,

control of a governor to shift the operating position of said device.

22. In a governing mechanism for a multiple-nozzle turbine, a plurality of independent means to open and close said nozzles, a rotating controller device adapted to successively actuate said means, fluid-pressure means to shift the operating position of said device, and a governor-shifted valve to control said fluid-pressure means and move said device in correspondence with said changes of the load.

23. In combination with a turbine, means to control the admission of motor fluid against a rotary element therein, a controller device acting on said means to vary the supply of motor fluid, a spring cooperating with fluidpressure means, means tending to move said device in one direction, a governor, and fluidpressnre means, under the control of said governor which acts to move said device in opposition to said spring and pressure means.

2%. In a controller mechanism for a multiple-nozzle turbine, a cylinder, a piston therein, means to adjust the position of said piston in the cylinder, and means which engage and are actuated by said piston to open and close said nozzles.

25. In a controller mechanism for a multiple-nozzle turbine, a cylinder, pressure inlet and exhaust ports therein, a movable piston between saidv ports, and means to open and close the turbine-nozzles comprising valves actuated by said piston and operating to open or close passages, leading from said cylinder, to one of said ports.

26. In a controller mechanism, a cylinder having pressure inlet and exhaust ports and a plurality of normally closed conduits opening thereinto, valves to close said conduits, and a controller-piston between the ports in said cylinder which successively actuates said valves to open communication between their conduits and one end of said cylinder.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

JAMES WILKINSON.

IVitnesses:

R. D. JOHNSTON, Nonin WeLsn.

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