US2685428A - Automatic speed regulator for turbines - Google Patents

Description

Aug. 3, 1 54 H. R. TRESSL 2,685,428

AUTOMATIC SPEED-REGULATOR FOR TURBINES Filed July 2, 1948 4 Sheets-Sheet 1 I I II I/ I/ II 47 44 'F/G. i.

[\hhhhil 3 6/ 4/50 INVENTOR. i HENRY E. 779555;,

LA ATTORNEYS.

Aug. 3, 1954 H. R. TRESSL 7 2,635,428

AUTOMATIC SPEED REGULATOR FOR TURBINES Filed July 2. 1948 4 Sheets-Sheet 2 1 v \MMMIHQI INVEN TOR.

HENEY E. Tess-s4,

BY 7 %%%M Wm *WM Aug. 3, 1954 H. TRESSL AUTOMATIC SPEED REGULATOR FOR TURBINES 4 Sheets-Sheet 3 Filed July 2, 1948 mmvrozi HENRY P 779E861,

ATTG/P/VE'YS.

H. R. TRESSL.

AUTOMATIC SPEED REGULATOR FOR TURBINES Aug. 3, 1954 A. t e e h s s t e e h s 4 Filed July 2 1948 Wm M a r W4 n 5% M,

Patented Aug. 3, 1954 AUTOMATIC SPEED REGULATOR FOR TURBINES HenryR. Trcssl, Roundup,- Mont.

Application July 2, 1948; Serial No. 36,758

4 Claims. 1 .This invention relates to' prime movers of the turbine type, and more particularly to automatic speed control, means for a turbine.

Amain object ofthe invention is to provide a noveli and improved speed control means for a turbine; said speed control means being very simple in construction, reliable in operation, and very easy to adjust for obtaining the desired speed of operation of the turbine rotor. V

,A further object of the invention is to provide an improved turbine device of the automatic speed controlled type which accurately maintains its rotor-speed substantially constant over a wide range of loading conditions, and which is particularly suitable for use with electrical generators, A

said turbine device involving only a few parts, being easy to adjust for obtaining a desired speed. of rotor operation, being rugged in construction, and requiring only a minimum amount of human supervision.

Further objects and advantages of the-invention will become apparent from the follow-ingde- .scription and claims, and from theaccompany- .ing drawings, wherein:

Figure 1 is a cross-sectional detail view with parts broken away, taken on line 1-4 of Figure 3 showing the turbine rotor and the speed regulating mechanism therefor.

Figure 2 is an enlarged cross-sectional detail .view taken on line 2-2 of Figure 3.

Figure 3 is a side elevational view partly broken away of a turbine constructed in accordancewith the present: invention.

Figure 4 is a fragmentary side elevational View of the rotor and speed controlling mechanism therefor of the turbine of Figure 3 with the parts in positions corresponding to substantially no load on the turbine.

Figure 5 is a view similar to Figure 4 with the parts in positions corresponding to partial loading of the turbine.

; Figure 6 is a View similar to Figure 4 with the parts in positions corresponding to full loading of the turbine.

Figure '7 is a view similarto .Figure 4. but illustrating a modified form of speed-controlled turbinestructure according to the present invention.

Figure 8 is a view generally similar to Figure '7 but illustrating still another form of speedcontrolled turbine structure according to the present invention.

Figure 9 is a viewgenerally similar to Figure lbut showinga further form of speed-controlled turbine structure according to this invention.

2 Figure 10 is an enlarged cross-sectional detail view taken on line Hl-I0 of Figure 1.

Figure 11 is a side elevational view of the structureshown in Figure 9.

Referring to the drawings, and more particularly to Figures 1, 2 and 3, ll designates a' supporting frame which may be rectangular .as shown, or may have any other suitable shape, and which includes a pair of parallel horizontal upper bar members l2, l2. Clamped transversely to the bar members l2, 12 by means of U-bolts l3, I3 is a sleeve member M in the respective end portions of which are secured the bearing bushings l5, l5. Journalled in'bushings I5, I5 is a shaft [5, said'shaft being provided with the end collars ll, H which rotatably engage the ends of sleeve member'l i and prevent shaft I 6 from moving endwise. Secured to one end of shaft l6ris a pulley l8.

Desi nated generally at 19 is a fork member having depending arms 26 and 2|, and having'an upstanding intermediate arm 22. The arms 20 and 2| are formed attheir upper ends with vertical slots 23'," 23, and adjustably clamped to the arms atsaidslots by means of clamping'bolts 24 are bearings '25,. 25 rotatably mounted on the sleeve member In. Secured on the sleeve member 44 outwardly adjacent to the respective bearings 25, '25 are stop collars 26, 26 which prevent the fork member l9 from'moving longitudinally with respect to said sleeve member. The arms 20 and 21 are provided with adjusting screws 21, 21 abutting the bearings 25, 25 at the lower surfaces of said: bearings for adjusting the bearings 25, 25 along the slots 23,23.

Journalled in bearings 28, 28 secured to the lower portionsof. arms 20. and 2| is a shaft 29 which carries the turbine rotor 30, said rotor beingsubstantially conventional in structure and having the peripheral arcuately' curved impeller blades 3 I.

" Secured to frame H is a shield 32 which covers the upperportion of rotor 39 and is suitably shaped to allow said rotor to swing through a substantial angle around the axis of shaft l6. Shaft .ie'carries a pul1ey-33 which is coupled to pulley it by a crossed belt 3 Secured to shaft 29 outwardly adjacent the bearings 28, 28 are stop collars 35, 35 which prevent substantial endwise A guard housing 34 surrounds the pulleys 33, It and belt 34.

Secured to the top of frame H is a bracket member '36 formed with an offset top arm 31 opposing the upstanding arm 2201f fork member iiiand provided-with an adjustable stopscrew 38 engageable with arm 22. Designated at 39 is an upstanding bar member carried by frame II, and connecting the top portions of arm 22 and bar member 39 is a spring 40 which biases fork member I 9 clockwise, as viewed in Figure 3, so that arm 22 normally abuts the end of screw 38. Secured to the lower end of arm 2! of the fork member is a rearwardly extending bar 4] on which may be adjustably secured a weight 42, which also acts to bias fork I9 clockwise, as seen in Figure 3.

Secured in the lower portion of frame H is a nozzle 43 which is preferably rectangular in cross section and which is directed toward the bottom impeller blades 31 of rotor 30 so as to impart counterclockwise rotation to the rotor as viewed in Figure 3, when a fluid jet is discharged therefrom. In the normal position or fork [9, with arm 22 abutting the end of screw 38, only the upper portion of the jet engages the impeller blades 3|. The aXis of the nozzle is upwardly in-' clined to a position, substantially tangential to rotor 30 in its normal position. As the fork l9 swings counterclockwise around the axis of shaft l6, as viewed in Figure 3, the lower portion of rotor 39 is brought more and more into the path of the fluid jet emerging from nozzle 43 due to the fact that the radial distance from the bottom peripheral portion of rotor 30 to the axis of shaft 16 is much greater than the radius of the rotor 30.

Shaft l 6 is connected to a suitable load, as for example, a generator 44, as shown in Figures 4, 5 and 6. Figure 4 shows the positions of the parts at no load. The nozzle jet, indicated at 45, only partially engages the impeller blades of the rotor 39 but furnishes enough energy to revolve the rotor, since the resistance to rotation thereof is quite small. As load is applied to generator 44, the resistance to rotation developed in rotor 38 increases, and the jet 45 provides a force sufiicient to overcome the biasing force of spring 46, the moment between the jet and the axis of shaft [6 overcoming the restraining moment of said spring. This causes the fork I9 to swing counterclockwise from the position of Figure 4 to the position of Figure 5, carrying the rotor 30 to a position wherein an increased cross-sectional area of the jet is engaged by the rotor blades. Since the force applied to the rotor blades by jet 45 is proportional (at constant fluid pressure) to the area of the jet acting on the blades,

the torque applied to rotor 30 is increased, thereby compensating for the increased loading of the generator without reducing the rotational speed of the rotor. As the generator load is increased to full load, fork i9 is swung further counterclockwise due to the increase in resistance to rotation of rotor 38, to the position of Figure 6 wherein the entire cross-sectional area of the jet 4-5 acts on the impeller blades of the rotor. The increased torque on the rotor again compensates for the increased loading of the generator, and the rotor speed remains substantially unchanged. As the loading on the generator decreases, the spring 40 returns the fork H! to that position wherein the jet area engaging the impeller blades provides sufficient force to rotate rotor 36 under its load and to balance the moment exerted on fork 19 by the spring 4!].

From the above discussion, it will be apparent that for a constant fluid pressure at jet 45, the

rotor speed at no load may be set by adjusting the stop screw 38 so that the jet #5 just engages the blades of the rotor 30. The amount of torque compensation provided under loading conditions will then depend upon the strength of spring 40 as well as upon the relative radial distances of spring 40 and the lower peripheral portion of rotor 30 from the axis of shaft l6. By a proper choice of spring 40 the rotational speed of rotor 30 between no load and full load conditions may be therefore held constant.

Secured to the top of frame I l on the opposite side of arm 22 from bracket member 35 is a second upstanding bracket member 36' provided with a stop screw 38' engageable by arm 22 to limit counterclockwise rotation of fork member l9. Stop screw 38 is employed to prevent rotor 30 from engaging shield 32 when the turbine is overloaded.

Oscillations of fork I9 around its equilibrium position for a given condition of loading are damped by means of a damping collar comprising arcuate segments 46 and 41 hinged together at ts and encircling the intermediate portion of sleeve member M. The segments 45 and M are formed with opposing lug portions is and 5B and a screw bolt passes through lug portion 49 and threadedly engages lug portion 59. Encircling screw bolt 5! and bearing between the head of said bolt and the lug 49 is a coiled spring 52, which provides a frictional gripping force of the segments 46 and 4"! on the sleeve member 14. Segment 46 is formed with an upstanding tapped lug 53 through which a stop screw 54 is threaded, said stop screw being engageable with fork 19. Segment 4'! is formed with a depending lug 55 provided with an adjustable stop screw 56 also engageable with fork I9. Angular movement of fork IS with respect to sleeve member I4 is damped by the frictional engagement of segments and 47 with said sleeve member, the degree of damping being adjustable by means of screw bolt 5| and the amount of undamped permissible movement of fork 19 being adjustable by means of stop screws 54 and 56.

If the embodiment illustrated in Figure 7, the shaft I6 carries a sprocket 5'! and shaft 29 carries a sprocket 58. Secured to fork 19 adjacent sprocket 53 is a plate member 59 on which is rotatably mounted an idler sprocket 60. A sprocket chain 3| extends around sprocket 51 and idler sprocket Gil, meshing with sprocket 58, as shown in Figure '7. Pivotally connected to the lower end of fork arm 2i is a link rod 62. Desi hated at 63 is a control valve interposed in the nozzle conduit 43, said valve having an operating lever 64 which is pivotally connected to link rod 62. Valve 63 is normally open only partially and gradually becomes further open when lever 64 is rotated clockwise from the position shown in Figure 7. In this embodiment the nozzle 43 is inclined upwardly at a steeper angle than in Figure 4 and is arranged so that the full cross-sectional area of the nozzle jet impinges on the rotor blades at all times, but the jet flow rate is regulated by valve 63. Under no load conditions, the rate of flow is low. As the load increases, fork l9 swings counterclockwise in the manner previously described, whereby link rod 62 rotates valve lever 64 clockwise, causing the fiow rate to increase and increasing the torque applied to the rotor. The turbine is thus enabled to sustain the increase in loading without reducing its speed. As in the previous embodiment of the invention, the speed may be held constant between no load and full load conditions by a proper choice of biasing spring 46.

In the embodiment of Figure 8, shaft It carries a gear65 which directly meshes with a gear 66 carried by shaft 29. The nozzle 43 is arranged in the same manner as in the embodiment of Figures 1 to 6 and the operation of the turbine is the same as in said former embodiment, the turbine rotor blades being engaged only partially by the nozzle jet at no load and being fully engaged by said jet at full load, the spring 46 regulating the equilibrium speed of the turbine rotor over the range of different loading conditions, whereby the speed may be held constant by a proper choice of spring.

In the embodiment of Figure 9, the turbine rotor 39 is mounted separately from the speed regulating mechanism and is journalled in upstanding supports shown at 61, 61. The speed regulating mechanism comprises a frame 68 which is pivotally mounted on a horizontal sleeve member 14, said sleeve member being clamped to a suitable support, not shown. The shaft 16 is journalled in sleeve member Id and carries a pulley 18 coupled by a crossed belt 34 to the pulley 33 carried on a shaft 29 journalled in the lower portion of frame 68. The rotor shaft, shown at 69, is connected by a universal joint Hi to a spline rod H which is slidably received in an internally splined sleeve member 12. Sleeve member 12 is connected by a universal joint 13 to the end of shaft 29. The nozzle conduit, shown at 14 includes a flow control valve 75 having an operating lever i5. Lever I6 is connected by a link bar H to the lower end of frame 68. Frame 68 is formed with an upstanding arm 22. Connected to the top end of arm 22 is the speed regulating spring 46, which functions in the same manner as in the embodiment of Figure '7 to bias the valve 75 toward a partly closed position. As in Figure '7, the nozzle 43 is arranged so that the turbine blades are engaged by the full cross-sectional area of the nozzle jet at all times. When there is no load on the generator 44, reduced flow occurs at the nozzle 43. When the load on the generator is increased, demanding more torque on the rotor blades, the rotor slows down momentarily, al-

lowing increased torque to be developed at shaft 1! 29, said increased torque creating a moment on frame 66 with respect to the sleeve M which overcomes the biasing moment of spring 49 and rotates frame 68 to a position opening valve 15 more fully. provides the necessary increased torque on the rotor blades to restore the turbine to its desired speed. As in the embodiments previously described, the steady state speed of the turbine rotor may be controlled and held constant by a proper choice of spring 49.

While certain specific embodiments of automatic speed regulating mechanism for turbine rotors have been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore, it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims.

What is claimed is:

1. In combination, a turbine rotor, a frame, a support, means swingably mounting said frame with respect to said support, means rotatably mounting said rotor on said frame for swinging This increases the flow at jet 43 and in said frame, coaxially with said swinging axis, a stationary nozzle furnishing fluid to the periphcry of said rotor and including a flow-controlling valve, means linking said frame to said valve, means biasing said frame to a position partially closing said valve, whereby a relatively small amount of fluid flow normally occurs in the nozzle, and means coupling said rotor to said shaft.

2. In combination, a turbine rotor, a frame, a support, means swingably mounting said frame with respect to said support, means rotatably mounting said rotor on said frame for swinging movement therewith on an axis offset from the swinging axis of the frame, a shaft journaled in said frame, coaxially with said swinging axis, a stationary nozzle furnishing fluid to the periphery of said rotor and including a flow-controlling valve, means linking said frame to said valve, means biasing said frame to a position partially closing said valve, whereby a relatively small amount of fluid flow normally occurs in the nozzle, means coupling said rotor to said shaft, and

adjustable damping means frictionally secured on said support and engaging said frame, said damping means preventing free oscillation of said frame.

3. In combination, a turbine rotor, a frame, a support, means swingably mounting said frame with respect to said support, means rotatably 0 movement therewith on an axis offset from the 7 swinging axis of the frame, a shaft journalled mounting said rotor on said frame for swinging movement therewith on an axis offset from the swinging axis of the frame, a shaft journaled in said frame coaxially with said swinging axis, a stationary nozzle furnishing fluid to the periphery of said rotor and including a flow-controlling valve, means linking said frame to said Valve, means biasing said frame to a position partially closing said valve, whereby a relatively small amount of fluid flow normally occurs in the nozzle, and positive drive means coupling said rotor to said shaft.

4. In combination, a turbine rotor, a frame, a support, means swingably mounting said frame with respect to said support, means rotatably mounting said rotor on said frame for swinging movement therewith on an axis offset from the swinging axis of the frame, a shaft journaled in said frame coaxially with said swinging axis, a stationary nozzle furnishing fluid to the periphery of said rotor and including a flow-controlling valve, means linking said frame to said valve, means biasing said frame to a position partially closing said valve, whereby a relatively small amount of fluid flow normally occurs in the nozzle, respective sprockets secured to said rotor and said shaft, and a sprocket chain engaged on said sprockets.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 96,182 Anderson Oct. 26, 1869 525,440 Bookwalter et al. Sept. 4, 1894 549,848 Doolittle Nov. 12, 1895 556,476 Richardson Mar. 17, 1896 1,071,513 DeMill Aug. 26, 1913 1,505,909 Melin et al. Aug. 19, 1924 FOREIGN PATENTS Number Country Date 122,373 Austria Apr. 25, 1931

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