US1669108A - Governing mechanism for elastic-fluid turbines - Google Patents

Description

May 8, 1928. 1,669,108

D. F. WARNER GOVERNING MECHANISM FOR ELASTIC FLUID TURBINES Filed Sept. 13, 1926 Inventor": D onaiol F Wanner,

s M44 HLS Attorney.

35 quires Patented e., 8,1928.

v 1,669,108 UNITED STATES PATENT' OFFICE.

DONALD I. W O! mum, HBBAGHUSETIS, ASSIITGHOI TO GENERAL W eonm, A

OOBPOBA'I'IOIF OF YORK.

aovnmwme mm FOB ELASTIC-mm Application ma September 1:, 1026. as... 134,952.

The present invention relates to governin mechanisms for controlling the speeed o J prime movers, such as elastic fluid turbines and the like, and especially to governing 6 mechanisms of the type known generally as single actuating governing mechanisms, it being understood that by such govermng mechanisms I mean those wherein the valve means which controls the admission of operatin fluid to the prime mover is positioned by uid ressure acting against a blasmg force, suc as the force of a spring. In such governing mechanisms, the amount of valve 0 ening is determined by the value of the flui pressure which in turn is controlled by a primary governor, such as a speed governor.

In connection with the operation of a valve mechanism of this type, there is a definite fluid ressure for every load on the machine,

i. e., or every valve opening, andfor theoretically perfect operation, whenever the load changes thereby bringing the primary overnor into action to efiect a change in the uid pressure, the governin mechanism should respond instantly to t e change in fluid presure to modify the position of the valve means. However, in actual practice, it is found that due to inherent characteristics of the governing mechanism, such as, for example, friction and reaction of the elastic fluid on the valve means, the valve means will not respond immediately to small pressure changes ut on the other hand resuflicient pressure change to overcome the friction and other eflects tending to hold the parts to be moved against movement. For example, suppose the valve means is operating at a point which requires a pressure of a certain value to maintain it in the desired position and that the friction eflect and other eifects at this point are such that a change in pressure of or X lbs. is required in order to effect movement of the parts to be moved. This means, therefore, that the pressure must change by an amount equal to X lbs. before an correcting efiect bv the governing means wi 1 take place. As a result, therefore, there is a gap or speed range over which the governor has no control of the valve gear motion and hence there exists a tendency to r uire a too great F speed change on the part of t e primary governor before the valve means operates.

The object of the present invention is to provide an improved construction and arrangement of governing mechanism whereb the change required on the part of the primary governor to effect 0 ration of the valve means is material? re uced, and for a consideration of what believe to be novel and my invention, attention is directed to the accompanying description and the claims ap ended thereto.

n the drawing, Fig. 1 is a diagrammatic view of a regulating means embodyin the invention, and Fig. 2 is a similar view s owing a modification.

Referring to the drawing, 5 indicates the admission end of an elastic fluid turbine to which elastic fluid is supplied by a suitable valve means 6 which is opened and closed by turning movements of a cam shaft 7 The valve means and cam arrangement for operating it may be of the same neral as that shown in the patent to 15 D. Dic lnson and R. G. Standerwick, No. 1,560,416, dated November 3, 1925, or it may be of any other suitable type. The turbine shaft is indicated at 8 and the oil tank is indicated at 9. The illustration of the turbine and regulating means is wholly diagrammatic. The turbine casing 5 and the shaft 8 are not shown in correct relation to each other but the turbine casing is brought around into the plane 6f the paper in order to illustrate more clearly the arrangement of the governor mechanism and its connection to the turbine valve gear. On the end of cam shaft 7 is a pinion 10 which meshes with a rack 11 formed on the upper end of a rod 12. The lower end of rod 12 is connected to a piston 13 which slides in a suitable cylinder 14. Arranged between the upper side of piston 13 and the cover plate 15 of cylinder 14 is a spring 16 which biases piston 13 toward the lower end of cylinder 14 and the valve means 6 toward closed osition. With the piston in the position s own in the drawing, the valve means is partly open. The arrangement is such that when piston 13 moves u ward, it opens valve means 6 and when it moves downward it effects the closing of the valve means. Any suitable valve means may be used in connection with my invention, the arrangement illustrated being only by way of example.

On turbine shaft 8 is a worm 17 which meshes with a worm wheel 18 mounted on a vertical shaft 19. Shaft 19 is mounted in suitable bearings, one of which is indicated at 20, and at its lower end it is connected to drive an oil pump 21 located 1n. tank 9. Oil pum 21 takes oil from tank 9 through a sultab e intake strainer 22 and delivers oil through a conduit 23 to a pipe 24. Connected to pi e 24 is a pressure relief valve 25 which d scharges back to tank 9 and which is set to maintain in pipe 24 a certain desired pressure.

Pipe 24 delivers oil through a non-return valve 26 and an orifice 27 in a plate 27" to a pressure pipe 28 and a b as pipe 29 which. branches therefrom. mce there is essentially a constant pressure in pipe 24, oil will be delivered t rough orifice 27 to pipes 28 and 29 always at a definite rate, depending upon the pressure exlstm 1n such ipes. Pipe 28 is connected to cyllnder 14 beneath plston 13 and conveys pressure to the underside of the piston for e ecting operation of valve means 6. Bypass pipe 29 is connected to a pilot valve structure A comprising an annular chamber 30 in the inner wall of pilot valve casing 31. In casing 31 is a bushing or sleeve 32 provided with holes 33 located in alignment with chamber 30. Bushing 32 extends throughout the length of casing 31 and is connected at its upper end to a lever 34 which is fulcrumed on the upper end of an arm 35 which in turn is pivotall sup orted on a flange at the base of pi ot -va ve casing 31. Inside bushing or sleeve 32 is a pilot valve 36 which is 1n the form of a tube or sleeve and is connected at its lower end to the weight arms 37 of centrifugal eed governor B so as to turn therewith. is

eed governor is the primary governor for t e turbine. For the purpose of this diagrammatic illustration, I have shown weight arms 37 pivotally connected directly to the lower end of pilot valve 36. This direct connection or any other suitable connection may be used. In actual practice, I prefer to use the specific arrangement disclosed in the application of E. D. Dickinson, Sr. N 0. 692,615, filed Februar 13, 1924. The speed governor is connected to and is driven by shaft 19 whereby it is rotated at a s eed ro ortional to the speed of the tur ine. Vit this arrangement pilot valve 36 rotates with the speed governor. The upper end of pilot valve 36 terminates adjacent to the to edge of holes 33 which communicate wit annular chamber 30 and serves to cover such holes to a greater or lesser extent. When the speed increases the pilot valve is lowered in bushing 32 to uncover holes '33, and when the s eed is decreased, the pilot valve is raise in bushing 32 to cover holes 33. Lever 34 is connected by a rod 38 to a late 39 which forms the upper end of a be ows structure 40. The lower end of bellows structure 40 is connected to a base plate 41 with a fluid-tight connection. Rod 38 extends loosely through the opening in base plate 41. Mounted on base late 41 is a casin 42 which forms with t e base plate a sea ed chamber 43 in which bellows 40 is located. The up r end of casing 42 is provided with a hol ow coupling 44 having an car 45 to which is ivotally connected one end of an'arm 46, tlie other end of arm 46 being rigidly connected to rod 12. Chamber 43 is connected to pressure pipe 28 by a suitable flexible connection 47, the connection to chamber 43 bein through hollow coupling 44 and a suita le opening 48. With this arran ement, it will be seen that bellows 40 is su jected at its up er end to the pressure existing in pipe 28 w ich is the pressure applied to piston 13. Inside bellows 40 is a sprin 49 which opposes collapsing of the be lows. The pressure in chamber 43, acting on bellows 40 and tending to collapse it, is balanced by the bellows and by spring 49 so that at a certain pressure plate 39 occupies a definite position in casing 42. When the ressure in chamber 43 increases, plate 39 Wlll be moved downward thus lowering the left hand end of lever 34 and hence pilot valve sleeve 32 and when the pressure In chamber 43 decreases, plate 39 will be moved upwardly thus raising the left hand end of lever 34 and pilot valve sleeve 32. This movement of plate 39, lever 34, and sleeve 32 due to changes in pressure, it will be seen, is effected independentl of casin 44 and lever arm 46.

ith the ziove described arrangement, when the turbine is running ump 21 supplies oil through pi e 24 an orifice 27 to pressure pipe 28 an bypass pipe 29. The pressure of the oil in pipe 24 is fixed at a definite value by pressure-relief valve 25 so that oil is supplied to pipes 28 and 29 at a definite pressure. 011 escapes continuously from pipe 29 through ports 33 to the interior of pilot valve casin 31 from whence it runs down through tubu ar pilot valve 36 to tank 9. The pressure in pipe 28 and hence that to which piston 13 is subjected depends directly on the rate at which oil is ypassed through conduit 29 and this in turn depends directly upon the extent to which ports 33 are uncovered. The extent to which ports 33 are uncovered depends upon the relative position of pilot valve 36 to ilot valve bushing 32.

ssume that the turbine is running, piston 13 being held in a certain position b the oil pressure in pipe 28 so as to hol the valve means open to a certain extent and that due to an increase in load the speed of the turbine decreases. When this occurs the governor weights 37 move inwardly somewhat. This raisestubular ilot valve 36 relatively to sleeve 32, there covering to a greater extent ports 33. This decreases the v x 5 rate at which oil can escape through bypass pipe 29, with theiresult-that the ressure in ipe 28 increases. The increase ressure 1s applied to, the lower side of iston 13 raising it somewhatto open furt er valve means 6, thereby admitting additional elastic fluid to the turbine in an efl'ort to restore it to its former speed.

When the pressure in pipe 28 increases, the increased pressure is applied to bellows 40 serving to collapse it omewhat against the action of spring 49. d T is serves to move the left hand end of lever 34 downwardly,

thereby lowering pilot valve sleeve 32 and closing further the ports 33. Thus it will be seen that as soon as pilot valve 36 moves upwardly and the pressure in conduit 28 begins to increase the increased pressure serves to effect a further closing oil of ports 33, thus augmenting the action of the governor in increasin the pressure applied to piston 13. In 01; or words, as soon as the pressure in conduit 28 begins to increase due to upward movement of pilot valve sleeve 36, such increase in pressure sets into action means which serves to assist the governor in eifecting movement of piston '13. As a result, the friction and other forces tending to hold piston 13 from movement are overcome quickly whereby prompt response of the governing mechanism to the speed changes is obtained. When piston 13 moves upwardly, itcarries with it the arm 46 and such upward movement lifts the left hand end of lever 34, thereby raising the sleeve 32 relatively to pilot valve 36 to again uncover somewhat the ports 33. Thus it operates as a follow-up mechanism to restore the ports to a position such that there will be maintained under piston 13 a pressure sufficient to maintain it in its new osition against -the action of spring 16, t e new position being one such that valve means 6 is held open to an extent to supply sufficient stearim to the turbine to carry t e increased loa When the load decreases, the speed of the turbine tends to increase, thus throwing weight arms 37 outwardly and lowering pilot valve 36. This serves to uncover somewhat ports 33 permitting oil to escape more rapidly through bypass pipe 29, thereb lowerin the pressure under piston 13 whic is then owered by spring 16 to decrease the opening of valve means 6. When pilot valve 36 moves downwardly decreasing the pressure in conduit 28, the pressure is lowered in chamber 43 whereupon spring 49 distends somewhat bellows 40, thus lifting pilot valve sleeve 32 to uncover further ports 33. This additional uncovering of ports 33 serves to augment the action of the speed governor after the manner explained above so as to 'efl'ect prompt action of the governing mechamsm in response to the increased speed.

In connection with the construction illustrated, it will be seen that lever 34 and its connection to rod .12 provides a usual arrangement of follow-up connection'to prevent overtravelof the governing mechanism and that bellowsAO and .casing 42 form an intermediate adjustable sectlon in the follow-up connection. Also, it will be seen that pilot valve sleeve 36 and pilot valve bushing 32 formfin substance two valve members. the movements of either of which serves to effect change in pressure in conduit 28. v i

In Fig. 2 is illustrated a modification wherein the pressure responsive device cor responding to the bellows 40 of Fig. 1 is in the form of a piston 51 which moves in a cylinder 52 against the action of a spring 53. Cylinder 52 beneath piston 51 is connected by a pi e 54 to oil chamber 30, the piston being t us subjected at all times to the oil ressure in the governing system. Carried y istons 51 is a stem 55 which at 'its upper en is pivoted to one end of a lever 56 fulcrumed at 57 and having its other end connected to a lever 34 corresponding to lever 34 of Fig. 1. Otherwise the arrangement shown in Fig. 2 ma be the same as that shown in Fig. 1 and t e same reference numerals with the exponent a added have been used to designate corresponding parts.

The Fig. 2 arrangement operates after the manner of the Fig. 1 arrangement, piston 51 being moved in response to chan in ressure in the system and so moving bus ing or sleeve 32 to augment the action of the speed overnor.

This In cation has the advantage that since piston 51 is located in close proximity to the speed governor it responds very quick ly to pressure changes inaugurated by the speed governor.

- In accordance with the provisions of the patent statutes, I have described the princi le of operation of my invention, together with the apparatus which I now consider to re resent the best embodiment thereof, but desire to have it understood that the apparatus shown is only illustrative and that the invention may be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the United States, is

1. The combination with a prime mover having a governing mechanism comprising a movable element, means biasin it in one direction, means for supplying uid under pressure to move said e ement in opposition to said biasing means, and a governor controllin said second-named means, of means contro ed by changes in pressure of said fluid for augmenting the action of said governor. 1

2. The combipation with a prime mover having a governing mechanism comprising'a movable abutment a spring biasing it in one direction, a conduit for supplying flu d under pressure to said abutment to move it against the action of said spring, a valve means which controls the pressure in said conduit, and a governor connected to said valve means, of means responsive to change in pressure in said conduit for augmenting the action of the governor on said valve means.

3. The combination with a prime mover having a governing mechanism comprising a movable abutmen a. s ring biasing it in one direction, a con uit or supplying fluid under pressure to said abutment to move it against the action of said spring, a valve means which controls the pressure in said conduit, and a governor connected to said valve means, of a second valve means which also controls the pressure in said conduit, and means responsive to change in pressure of said conduit for eflecting movement of said second valve means in a direction to" augment the action of said governor.

4. The combination with a prime mover having a governing mechanism comprising a movable abutment, a spring biasing it in one direction, a conduit for supplying fluid under pressure to said abutment to move it against the action of said spring, a valve restoring bushing to augment the action of said vernor.

5. he combination with a prime mover having a governing mechanism comprising a movable abutment a "ring biasing it in one direction, a conduit or supplying fluid under pressure to said abutment to move it against the action of said spr' a valve means comprising a pilot valve :Ei a restoring bushing which controls the pressure in said conduit and a governor connected to said pilot valve, of means forming a followup connection for the restoring bushing, said follow-u connection including an intermediate ad ustable section, and means responsive to change in pressure in said conduit for eifecting movement of said intermediate adjustable section to augment the action of said governor.

In witness whereof, I have hereunto set my hand this tenth day of September, 1926.

DONALD F. WARNER CERTIFICA'IE 0F CORRECTION.

Patent No. 1,669,108.

DONALD F.

Granted May 8, 1928, to

WARNER.

p It is hereby certified that error appears in printed .sneciticatim oi the shove numbered patent requiring correction as follows: Page 4, line 22, claim 3, for the word "of" first occurrence read "in"; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 5th day of ,Iune, A. D. 1928.

. M. J. Moore, Acting Gon'nniasioner of Patents.

movable abutment a spring biasing it in one direction, a conduit for supplying flu d under pressure to said abutment to move it against the action of said spring, a valve means which controls the pressure in said conduit, and a governor connected to said valve means, of means responsive to change in pressure in said conduit for augmenting the action of the governor on said valve means.

3. The combination with a prime mover having a governing mechanism comprising a movable abutmen a. s ring biasing it in one direction, a con uit or supplying fluid under pressure to said abutment to move it against the action of said spring, a valve means which controls the pressure in said conduit, and a governor connected to said valve means, of a second valve means which also controls the pressure in said conduit, and means responsive to change in pressure of said conduit for eflecting movement of said second valve means in a direction to" augment the action of said governor.

4. The combination with a prime mover having a governing mechanism comprising a movable abutment, a spring biasing it in one direction, a conduit for supplying fluid under pressure to said abutment to move it against the action of said spring, a valve restoring bushing to augment the action of said vernor.

5. he combination with a prime mover having a governing mechanism comprising a movable abutment a "ring biasing it in one direction, a conduit or supplying fluid under pressure to said abutment to move it against the action of said spr' a valve means comprising a pilot valve :Ei a restoring bushing which controls the pressure in said conduit and a governor connected to said pilot valve, of means forming a followup connection for the restoring bushing, said follow-u connection including an intermediate ad ustable section, and means responsive to change in pressure in said conduit for eifecting movement of said intermediate adjustable section to augment the action of said governor.

In witness whereof, I have hereunto set my hand this tenth day of September, 1926.

DONALD F. WARNER CERTIFICA'IE 0F CORRECTION.

Patent No. 1,669,108.

DONALD F.

Granted May 8, 1928, to

WARNER.

p It is hereby certified that error appears in printed .sneciticatim oi the shove numbered patent requiring correction as follows: Page 4, line 22, claim 3, for the word "of" first occurrence read "in"; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 5th day of ,Iune, A. D. 1928.

. M. J. Moore, Acting Gon'nniasioner of Patents.

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