US2224321A

US2224321A - Hydraulic governing apparatus

Info

Publication number: US2224321A
Application number: US193487A
Authority: US
Inventors: Anthony F Schwendner
Original assignee: Westinghouse Electric and Manufacturing Co
Current assignee: CBS Corp
Priority date: 1938-03-02
Filing date: 1938-03-02
Publication date: 1940-12-10
Anticipated expiration: 1957-12-10

Description

Dec. 10, 1940.

A. F. SCHWENDNER nYDnAULIc eovERNiNG APPAIum'rUs` Filed Ilarch 2, 1938 2 Sheetg-Shee 1 INVENToR Rumeur F.' Scnweuausn.,

ATTORNEY Dec- 10. 19441 A. F. scHwENDNER 2.224.321

HYDRULIQ GOVBRNING APPARATUS Filed latch 2, 1938 2 Sheets-Sheet` 2 Patented Dec. 1 0, 1940 PATENT AOFFICE HYDRAULIC GovEnNmG APPARATUS Anthony F. Schwendner, Essington, Pa., assignor to Westinghouse Electric & Manufacturing Company, East Pittsb oi Pennsylvania urgh, Pa., a corporation Application March 2, 193s, serialNo. 193,487

22 claims. icl. 264-14) My invention relates to hydraulic governing apparatus for rotating machinery, such as prime movers, and it has for an object to provide apparatus of this character which is versatile from the point of view of meeting different operating requirements.

. A further object of my invention is to provide a pressure transformer governor with an impedance device capable of being arranged to sem cure standard or ordinary governing operation, sluggish or base load operation, and anticipating operation where sudden load changes are encountered. A further object of my invention is to provide vw a governor providing for isochronous operation or a desired degree of speed correction adjustment.

A further object of my invention is to provide a transformer governor` having impedance means v with connections to secure standard, base load, anticipating and isochronous operations of the governor.

A further object of my invention is to provide a governing mechanism including a pressure transformer, which utilizes a primary pressure to se? cure a secondary or regulating pressure bearing predetermined relation to the primary pressure, together with a servo-motor for actuating the admission valve-of a prime mover and including a pilot valve actuated by means of a relay, which, in turn, is operated by means including iluid under secondary pressure coming from the transformer. Y

In the patent to Zelov, No. 1,966,841, July 1'7,

1934, there is disclosed and claimed a pressure transformer and in my patent, 2,009,417, `July 30, 1935, there is disclosed and claimed two types of transformer governors utilizing the principle of the Zelov patent, one type providing for anticipatory operation, where sudden load changes are encountered, and the other type providing for sluggish or base load operation in order that frequency fluctuations may be suppressed and they application thereof to the governor prevented.

In accordance with the present invention, I provide a single transformer governor which may be readily adjusted, not only for anticipatory and base load operations, but also for standard and speed-correcting operations as well.

-These and other objects are eiected by my invention as will be apparent from the following descriptionand claims taken in accordance with the accompanying drawings, forming a part of this application, in which:

Fig. 1 is a side elevational view showing a prime moverwith my improved governor mechanism applied thereto;

Fig. 2 is a fragmentary vertical sectional view showing the transformer governor andtaken along the line II-II of Fig. 3; ;5

Fig. 3 is a vertical sectional view taken along the line III- III of Fig. 2 and showing, in addition to the transformer governor, the servomotor apparatus;

Fig. 4 is a sectional view taken along the line .10 IV--IV of Fig. 2;

Fig. 5 is a sectional view taken along the line V-V of Fig. 2; and

Fig. 6 is a diagrammatic view showing the passage connections for the pilot valve of the trans- 315 former governor.

Referring now to the drawings more in detail, in Fig. 1, there is shown transformer governor ap-l paratus, at 6, controlling the admission valve .1 of a prime mover, for example, the turbine, at 20 8, including a cylinder 9 and a rotor Ill.

The rotor Il) drives the impeller I3 (Fig. 3) to provide a source of fluid under pressure for reversed ow impeller apparatus, such as dis-' closed and claimed in the patent to Bryant, No. 2,035,689, March 31, 1936, the reversed ow impeller apparatus including an orifice I4 through which iiuid under pressure is supplied from the impeller. I3 to the pressure passage I5 in which the magnitude of pressure depends upon the effect of the inclined passage I6 formed in the rotor, the passagel I6 providing for the escape of fluid against the centrifugal head of such passage, and, therefore, providing for maintenance of fluid under pressure in the pressure passage I5 35 varying substantially as the square of the speed of the rotor, irrespective of fluctuations in the delivery pressure of the impeller I3, it only being required that the delivery pressure of the latter `shall befsufiiciently high and any excess of iiuid 40 escaping through the inclined passage I6. Fluid under pressure in the passagel5 is supplied to .the transformer governor, at I1, which provides a secondary or regulating pressure for actuation of the servo-motor, at I8, the latter being cons45 nected to the lever I9 of the admission valve 1.

The apparatus, at 6, preferablyincludes a multiplepart body 20 having passages, chambers, and cylinders formed therein, as hereinafter de. scribed, and provided with a cover 2| through .5o which the actuating rod of the servo-motor extends for connection to the valve lever I9 as shown in Figs. 1 and 3.

Referring to the transformer governor. at I1, the stationary or body structure thereof is pro- 55 passage I5 and having its upper end closed by the y vlded with a chamber 22 connected to the pressure bellows 23, the upper end of the latter being connected to the cover plate 24 and the lower end being connected to an abutment *plate 25. A spring 26 has its upper end connected to the abutment plate and has its lower end connected to the adjustable plug 21 carried by the threaded stem 28. By turning the stem in any suitable manner, the plug 21 may be positioned to secure a desired spring force or tension. The stem 28 also has an abutment 29 engaged by the bell crank 3l fulcrumed at 30a and which may be moved angularly about the latter by means of the push rod 3| actuated either by means of the hand wheel 32 or the speed changer motor 33. Thus. by changing the spring force or tension by any of the means referred to, the governor maybe adjusted.

The 'abutment 25 forming a closure for the upper end of the pressure chamber 22 has thrust bearing engagement, at 35, with respect to the lower end of the piston 36 arranged in the cylinder 36a formed in th body structure, the piston being turned in any suitable manner, as by a turbine wheel 31, to avoid the effects of static friction.

The spinner piston 36 is provided with upper and

lower piston portions

38 and 39.' In neutral, or cut-off position, the upper piston portion just laps the pressure port and the lower piston portion 39 just laps the exhaust port or connection 4I. The piston is reduced between the

piston portions

38 and 39, the reduction cooperating with the cylinder 36a to provide a secondary or regulating pressure chamber or source 42.

The pressure port 40 is supplied from any suitable source of fluid under pressure, for example, by the passage 40a from the impeller'` I3 and the exhaust port 4i is connected to the drainage apparatus. Fluid under secondary or regulating pressure is supplied from the chamber 42 by the supply passage or conduit 44 to the servo-motor apparatus, at I6. The body 20 is also provided with a passage 45 for connection to bleeder control mechanism where the governor is supplied for a turbine of that type.

4From the apparatus so fai'- described, it will be apparent that, if there is a change in primary pressure in the passage |5` incident to load change, the relationship of the force of such pressure and of the` spring` 26 acting on the abutment 25 changes and the spinner piston is actuated to bring about change in secondary or regulatdng pressure and actuation of the servo-motor apparatus,at.|6.

Referring now to the servo-motor apparatus, at I6, in Fig. 3, there is shown a pressure chamber 41 defined in part by upper and lower bellows elements 46 and 43a connected to an abutment plate 49, the upper bellows being 4of smaller diameter than the lower bellowsand the abutment plate, therefore, providing a pressure abutment tace forming a part of the enclosure o1' the pressure chamber 41 and providing for expansible and contractible operation of the latter with upward and Adownward movement of the abutment plate 49. A cup valve 66 is connected to the abutment plate 49 and it extends into the pressure chamber 6| .supplied with fluid under pressure by an orifice l2 from the chamber 62a eommunicatingwith the discharge of the impeller I3.

The lower end of the cup valvey 66 is normally closely disposed with respect to the upper end "of the pilot-valve 53 in the cylinder 54, the pilot valve having upper and lower piston portions 55 and 56 normally covering pressure ports 51 and 56 and an intermediate piston portion 59 normally covering the exhaust port 60.

The operating cylinder 6| has upper and lower admission and exhaust passages 62 and 63 connected to the ports 64 and 65 formed in the cylinder 54. An operating piston 66 fits the cylinder 6l and it is connected to a rod 61 Whose upper end is pivotally connected to the lever I9. The rod 61 is also connected to a lever 68 fulcrummed, at 69, and having an abutment 10 which engages underneath the abutment 1I, adjustably connected, as by screw threads, to the stem 11a attached to the upper end of the spring 12, the lower end of the latter being connected to the ring 13 whose upper surface is engaged by the abutment member 14 connected to the rod 15 having a conical head 16 at its lower end which engages the seat 11 formed interiorly of the cup valve 50.

A spring 19 bears against the lower end of the pilot valve 53, the latter being positioned due to the opposed forces of such spring and .ofthe uid pressure in the chamber 5I.

Normally, the pilot valve 53 occupies a neutral, or cut-ofi, position, the tendency of pressure of fluid to build up in the chamber 5I acting on the upper end of the pilot valve against the force of the spring 19 to provide for escape of fluid through the bore 53a, to the drain. Accordingly, the position of the pilot valve 53 is determined by the Acup valve 50, the position of the cup valve and the construction of the pilot valve, providing for forces acting on the latter to Y cause it to follow the cup` valve, constituting a relay arrangement.

If there is a. change in secondary or regulating pressure supplied to the pressure chamber 41,

the cup valve 50 moves with the result that the pilot valve 53 is caused to move; however, the force of the secondary or regulating pressure is not used directly to effect such movement but actuates said relay serving this purpose.

If the cup valve moves down, then the effect of such movement is to restrict the escape of fluid from the chamber 5I with the result that pressure building up yin the latter causes the pilot valve to move downwardly. On the other hand, if the cup valve rises, then the resistance to escape of flow from the chamber 5| decreases, lowering the pressure in the latter chamber and diminishing the force Ioi' such pressure acting on the upper end of the pilot valve 53, and the preponderating force of the spring 19'causes the pilotvalve 53 to move upwardly.-

Hence, the abutment 49, the cup valve 50, thev pressure chamber 5|, the upper end of the pilot y valve 53, the oricev52, and the valve relation existing between the cup valve and the upper end of the pilot valve provide a relay utilizing small changes 'in secondary or regulating pressure force to control the application of pressures to the pilot valve 53 such that the latter is moved as determined `by the positioning of the cup valve 56 in consequence otchange in secondary or regulating pressure.

Just as soon as thepilot valve 53 moves from neutral position, then the ports 64 and 65 are brought into relation to supply motive fluid to one end of the operating cylinder 6I and to exhaust from the other end thereof; thereby bringlng about movement of the operating piston 66,

consequent change in the force of the spring 12, the arrangement being such that, when the cup valve 58 is moved in consequence of change in secondary or regulating pressure, the operating piston will move until the force of the spring 12 is changed suniciently so that thelatter force and the force of the secondary or regulating pressure acting on the cup valve will be in equilibrium with the cup valve in position for neutral position of the pilot valve 53.

While the cup valve 50 for the servo-motor apparatus has been described as having its position determined by forces of the spring 12 and of the secondary or regulating pressure, it will be apparent that, if desired, other forces may be applied thereto. For example, there is shown a passage 8| extending within the lower bellows 48a and which may be used for supplying bleeder pressure to the interior of the bellows Where the governing mechanism is applied to a bleeder turbine'.

Referring now to the features of the transformer governor providing for diierent types of operation, namely, standard or ordinary operation, anticipating operatiomsluggish or base load operation, or isochronous operation, the upper piston portion 38 of the piston valve 36 has an upper abutment face 83 closing the upper prestween its valve and theaccumulator and is ,con-A nected to the supply passage 44, the third passage having a valve 93 therein. A fourth passage 94 connects the secondary or regulating pressure space or source 42 with the supply passage 44 and it includes an adjustable needle valve 95.

With this arrangement of passages and valves, it will be apparent that the impedance effect of the accumulator 89 may be avoided altogether,

as is the case for standard or ordinary operation; it may be exerted on the upper pressure chamber ,85 when anticipating governing is desired; or it l may be exerted'on the supply passage 44 for sluggish or base load governing.

For standard operation, the

valves

88 and 95 would be in full open position and the valves 9| and 93 would be closed, this being the relation to secure application of secondary pressure t0 the upper abutment face 83 without lag or impedance. If there is a change in primary pressure, the secondary pressure changes in consequence thereof, the abutment or pistonareas 25 and 83 maintaining the pressures in xed ratio for the reason that the force of primary pressureon the area 25 is balanced by that of secondary or regulating pressure on the area 183. By suitable choice of areas, a change in primary pressure may be accompanied by any desired magnified change in secondary or regulating pressure.

For anticipating operation, which is desirable where large changes in load are encountered, the

valve 88 is adjusted to provide a restriction be tween the secondary pressure source 42 and the upper pressure chamber, 85, the valve 9| is opened so that communication is established between the accumulator 89 and the upper chamber 85, the valve 93 is closed to interrupt the second passage 92 and the valve 95 is opened. This adjustment of the valves subjects the upper chamber to the impedance eiect of the accumulator.

In order that the impedance effect of the accumulator may be exerted on the supply passage 44, incident to sluggish or base load operation, further changes in the connections are effected, the valve 88 being opened. the valve 95 being adjusted, the valve 93 being opened, and the valve 9| being closed, whereby restricted communication is established between the secondary source or chamber 42 and the supply passage 44 by means of the needle valve 95 and the accumulator is brought into communication with the supply passage by means of the second passage 92.

The governor is also provided with a fifth passage 96 connecting the upper pressure chamber 85 and the lower pressure chamber 86, the passage containing an adjustable needle valve 91 and a cut-olf valve 98. A second accumulator 99 is connected to the passage 96 between the needle valve 91 and the lower chamber 86. To adjust the governor for isochronous operation, the valve 98 is opened and the valve 91 is adjusted so as 'to provide for the application of the impedance valve 91, the valve 88 would be opened fully so Vby means of the impeller I3, a source of fiuid under pressure, which source is used both for motive uid purposes and for the purpose of deriving the primary controlling or governing pressure, as well as a source of pressure for lubrication where the uid is lubricant, the primary pressure being supplied lby the passage |5 to the pressure chamber 22 whose upper end is closed by means of the movable abutment 25. The force of the primaryv pressure tending to move the abutment upwardly is resisted by means of the spring 26. The abutment 25 abuts the lower end of the spinner piston valve 36by means of the thrust bearing 35, the spinner piston valve being turned by a turbine element 31 in order to avoid the elects of static friction. The spinner piston valve cooperates with the valve cylinder to provide a secondary or regulating pressure source 42 which is placed in communication either with the pressure port40 or with the exhaust connection 4| in order to bring about change in secondary or regulating pressure. f/

Other means must be employed/'in connection upward movement o1' the spinner piston, the secondary or regulating pressure increases due to the pressure port being placed in communication with the secondary pressure source 42, but, with increase in secondary or regulating pressure, the forceV applied to the upper piston face 83 increases with the result that equilibrium of the spinner piston is restored with the latter in neutral position.

`If the valve 88 is adjusted and the accumulator 88 is connected to the upper pressure chamber 85, the secondary source or chamber 42 being in open communication by means of the passage 84 with the supply passage 44, then change in pressure in the upper chamber 85 will lag with respect to changes occurring in the chamber 42 with the result that sufficient over-travel operation of the spinner piston will occur to secure anticipating operation.

For standard operation, the accumulator 88 is isolated both from the upper pressure chamber 85 and from the supply passage 44 by closure of the valves 8| and 83, the secondary chamber or source 42 being in full communication with the upper pressure chamber 85 by means of the open passage 81 and with the supply passage 44 by means of the open passage 84.

Where base load governing is desired and the imposition of frequency fluctuations on the governor are to be avoided, then full communication of the secondary pressure source or chamber 42 with the upper chamber 85 is established by means of the passage 81, the valve 88 Abeing fully open, the accumulator 88 is isolated 'from the upper pressure chamber 851 by closure of the valve 8|, communication of the secondary pressure source or supply 42 by means of the passage 94 with the supply passage 44 is restricted by adjustment ofthe needle valve 85, and the impedance eiect of the accumulator 88 is exerted on the supply passage 44 by opening the valve 83. For isochronous operation, the apparatus is arranged as hereinbefore described for standard operation, that is, with a change in load, the secondary or regulating pressure supplied bythe governor changes to change the steam admission suitably -to the new load; however, with this arrangement, some change in speed is inherently necessary. Therefore, in addition to features providing for the standard arrangement, the governor includes additional features for correction of the secondary or regulating pressure so that the speed may bewho1ly or partly corrected or compensated at different loads.

More particularly, for isochronous operation of the apparatus, the valve 88 is opened so that iluid under secondary pressure is supplied through the passage 81 to the upper pressure chamber 85, the accumulator 88 is isolated both from the chamber. and the supply passage 44 by closure of the valves 8| and 83, the valve 85 is opened to establish full communication by means of the passage 84 between the secondary pressure source or chamber 42 and the supply passage 44, and the valve 88 is opened and the valve 81 is adjusted so as to provide for. restricted communication between the upperv and lower chambers, the accumulator 88 exerting its eiect on the lower chamber. 1

Preferably `the valve 88 is arranged, not only to open and close the'passage 88 as already described, but also to control communication of the lower chamber 88 with a drainage passage |00. To this end, in Fig. 5, the valve 88 is sh'own 2,224,321 movement of the abutment 25 and consequent 'I as being of the reciprocatory plstontype and has piston valve portions I 0| and |02, the piston valve portion |0| being arranged to open and close the passage 88 and the piston valve portion |02 being arranged to close the drain passage |00. With the piston valve portion |0| in the position closing the passage 88, the passage |08 formed in the piston valve aiIords communication of the lower chamber 88 -with the drain passage |00; and, with the piston valve portion |0| moved so as to fully open the passage 88, the piston valve portion |02 closes the drain passage |00. The spacing or the piston valve portions |0| and |02 to control the passages in the manner stated also makes it possible to secure partial opening of the passage 88 and partial communication of the lower chamber 86 with the drain, with the result that the pressure supplied. from the upper chamber 85 is reduced and only part correction in speed is obtained. Further opening of the piston valve portion |0| will bring the pressure in the lower chamber 88 closer to that existing in the upper chamber 85 until the valve, at 88, is fully opened, in which position, the piston valve portion |02 of the valve closes the drain and the pressure in the lower chamber will equal that in the upper chamber, thereby obtaining full isochronous operation.

The secondary or regulating pressure supplied to the passage 44, in accordance with any of the modes of effecting governing operation, is furnished to the pressure chamber 41 of the relay device for securing operation of the pilot valve or servo-motor, the arrangement being such that the secondary or regulating pressure does not 85 move the pilot valve directly b ut merely changes the relationship of forces acting thereon so thatA differential forces are brought into play to bring about movement of the pilot valve, with the result that the servo-motor is quite sensitive to 40 .small changes in secondary or regulating pressure. In other words, a `change in secondary or regulating pressure applied to the abutment 48 brings about either upward or downward movement of the cup valve 50 and the pilotvalve 58 moves in consequence of the change in pressure relation of the pressure in the chamber 5| and the pressure of the spring 18, with the result that the balanced relation of forces acting on the pilot valve is temporarily disturbed and the latter moves, movement of the pilot valve following that of the cup valve, movement downwardly being secured by the force of pressure in the chamber 5| preponderating over that of the spring 18 and upwardly due to preponderance of the spring force over the uid pressure torce.

With movement of the cup valve 50 in consequence of change in secondary or regulating pressure due to load change oi the turbine, the operating piston 88 is causedto move to change the 60 position of the admission valve, and, at the same time, the forcev of the spring 12 is being changed, this movement continuing until the force of the spring 12 and that of the secondary 0r regulating ,i pressure supplied to the cup valve are in equi-1.65 librium with the latter in position for neutrali` location of the pilot valve 88, at which time, thei admission valve will be in suitable position for the changed load. l

Standard.. anticipating, and base load opera- 70 tions are similar in the respect thata percentage the anticipating operation being used where large loadchanges are encountered to bring about overtravel of the spinner piston valve and'consequent over-travel of the admission valve so as to anticipate the change in load in the direction of change. Inthe case of base load or sluggish operation, the only effect is to place the impedance of the accumulator 89 on the supply line 44 so as to suppress frequency fluctuations and prevent the latter from being impressed on the governor. In the case of isochronous operation, the turbine. operates at the same speed at all loads, because the upper and lower piston areas 83 and 84 are equal, the force of the spring 26 is fixed, and the only other factor is the vforce of the primary pressure. Hence, to be in equilibrium, the primary pressure must be restored to its normal value corresponding to a -constant speed. The only eiect of the restriction in the passage 96 and the accumulator 99 is to introduce an impedance eiect acting on the lower chamber 86 during the transient stage of going from one load to another, there being a temporary speed change followed by nal adjustment of the apparatus to restore the speed of the turbine to its normal value at the new load. Isochronous operation is a special case of speed adjusting r correcting operation in which full speed correction or adjustment is made incident to load changes. As already pointed out, the valve means 98 may be manipulated so as to secure speed correction to any desired extent and to render speed correcting operation effective or ineffective. If such valve means is adjusted to interrupt the passage 9B and to afford communication of the lower pressure chamber 86 with the drain, then the` speed correcting arrangement is ineffective, the governor being operable only for standard, anticipating, and base load conditions;` and, if the valve means is adjusted so as to afford communication between the upper andlower pressure chambers, then the speed correcting arrangement is effective, the extent of speed correction being determined by adjustment of the valve means to vary the extent of communication of the lower chamber with the drain, restriction of the latter communication resulting in greater and greater speed correction until, with communication of the drain entirely interrupted, isochronous operation is secured. The valve means 98' makes it possible to change from an ordinary operating condition, such as standard operation, to isochronous operation Without stopping the turbine. Assuming that the turbine is running under standard operation, then, to effeet change therefrom to isochronous operation, it is merely necessary to adjust gradually the valve means, at 98, so that speed correction is gradually increased until full correction, corresponding to the isochronous condition, is secured.

If it is desired to effect a speed change adjustment of the governing apparatus, this is done by adjusting the force of the spring 26 by any of the means illustrated. l While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not solimited but is susceptible of various changes and modifications without .departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are specifically set forth in' the appended claims.

What I claim is:

l. Ina governor for prime movers of the type responsive means to control the supply of energy thereto, means for obtaining governing force varying as a function of the speed of the prime mover, a device for supplying iiuid under regulating pressure to said pressure-responsive means and including means movable in response to change in' governing force to change the regulating pressure in the same direction as` the governing force, means for applying the regulating pressure to the movable means so as to balance the governing force, whereby a change in governing force due to a change in load and speed of the prime mover is followed by a change in regulating pressure in predetermined ratio thereto, and means for applying the regulating pressure gradually to said movable means so as to be effective in the same direction as the governing force, thereby temporarily chang-lng the regulating pressure so as to operate the admission valve for speed correction of the prime mover allowing the gradually changing regulating pressure `effective in the same direction as the governing force to replace the action-of the latter i on said means to secure pressure balance with the prime mover speed corrected and the governing pressure restored to its normal value.

2. In a governor for prime movers of the type having an admission valve operated by pressureresponsive means to control the supply of energy thereto, means for obtaining governing force varying as a function of the speed of the prime mover, a device for supplying fiuid under 'regulating pressure to said pressure-responsive means and including means movable in response to change in governing force to change the regulating pressure in the same direction as the governing force, means for applying the regulating pressure to the movable means so as to balance the governing force, whereby. a change in governing-force due to a change in load and speed ofthe prime mover is followed by a change in' regulating pressure in predetermined ratio thereto, means for applying'regulating pressure gradually to the movable means in the same direction Ias the governing force, thereby temporarily changing the regulating pressure so as to operate the admissionvalve for speed correction of the prime mover and allowing the gradually changing regulating pressure acting in the same direction as the governing force to replace the action of the latter on said movable means to the extent of speed correction, and means for varyingthe ratioof the gradually applied pressure to the regulating pressure to vary the extent of speed correction.

3. In a governor for prime movers of the type having an admission valve operated by pressureresponsive means to control the supply of en.`

' that, when the governing force changes, the regulating pressure changes until the change in regulating pressure balances the change in governing force; and second means providing for the application of regulating pressure gradually to the aggregate and in the same direction as the governing force, thereby temporarily changing the regulating pressure so as to operate the admission valve for speed correction allowing the gradually changing regulating pressure acting in the same direction as the governing force to replace the action of the latter in opposing said iirst means when the speed of the prime mover is corrected and said first and second means are in balance.

4. In a governor for prime movers of the type having an admission valve, means providing a first force varying as a function of the prime mover speed, a transformer providing a regulating fluid pressure, and a device responsive to regulating fiuid pressure for controlling the admission'valve; said transformer including an aggregate movable from a neutral position, in one direction, to increase the regulating fluid pressure, and, in the other direction, to decrease such pressure; means providing for application of said first force to the aggregate; biasing means applying a second force to the aggregate in opposition to the first force; means providing for application of a third force to the aggregate in a direction opposed to that of said first force and dependent upon the regulating -fluid pressure; means responsive to change'in regulating fluid pressure incident to change 4from one load condition to another to provideV a fourth force opposing the thirdforce; and means providing for adiustment of said fourth force so that it may be equal to or less than the. third force for each load condition.

5. In a governing system for a prime mover having an admission valve and a pressure-responsive devicefor controlling the position ol" the admission valve, of provisions for supplying regulating pressure to the pressure-responsive device to eii'ect adjustment of the admission valve to meet a change in load with a. small change in speed of the prime' mover; said provisions comprising an element movable from neutral position, in one direction, to increase the regulating pressure, and in the other direction, to decrease the regulating pressure; means for developing a governing force dependent upon prime mover speed and for applying said force to said element in the direction of movement thereof; means for applying a biasing force in opposed relation to the governing force; and means for applying to Lthe element a third force dependent upon regulating pressure and in opposed relation to the governing force, whereby, with a change in load, the admission valve is adjusteduntil the change in third force balances the change in governing force; and provisions for effecting further adjustment ofthe admission valve for speed ad justment of the prime mover and comprising means for. applying to said element-and in the same direction as the governing force a speed adjusting fourth force dependent upon the regulating pressure; means for rendering the lastnamed means effective or ineective and for securing any desired ratio oi fourth' -force to third force over the range from zero to unity: and' means for effecting gradual. change in said fourth force relative to change in said third force to cause movement of said element and further change the regulating pressure to eiiect further adjustment o1' the admission valve until the prime mover speed is changed suiiiciently to change the governing force an amount equal to the change in the fourth force.

6. vThe combination with .a machine having a pressure-responsive controlling device, of means,

sure.'

providing a force dependent upon an operating characteristic of the machine, means providing a biasing force, means providingfiuid under regulating pressure and Afor supplying the latter to that changes in such pressure are applied concurrently as they occur, second means including a piston area for applying regulating pressure to said element in opposed relation to said first means, and means cooperating with said second means to secure delayed application thereby to said element of changes in regulating pressure.

7. In a governor for prime movers of the type having an admission valve, pressure-responsive device for operating the admission valve, means providinga governingforce dependent upon prime mover speed, means providing a biasing force, means providing fluid under regulating pressure and for supplying the latter to said pressure-responsive device, the last-named means including a piston valve acted on by said forces and movable in consequence of change of governing force to change the regulating pressure, said piston valve having first and second piston areas with the first area facing in the direction of the governing force, means for applying fluid under regulating pressure to the first and second piston areas, and means cooperating withvthe lastnamed means to provide for delayed application of changes in regulating pressure to the second piston area.

8. In a governor for prime movers of the type having an admission valve, means providing a governing force dependent upon an operating condition of the prime mover, a transformer providing a regulating fluid pressure, and a device responsive to regulating fluid pressure for controlling the admission valve: said transformer including an element movable from a neutral position, in one direction, to increase the fluid pressure, and, in the other direction, to decrease such pressure; means providing for the application of said governing force to the element in the path of movement thereof; biasing means exerting its effect on' the movable element in opposition to the governing force; opposed and equal first and second piston areas for the movable element; said first piston area facing in such a direction that pressure applied thereto exerts a force on the movable element in the same direction as the biasing means: means for applying regulating fluid pressure to the first piston area; and means -responsive to change'in regulating fiuid pressure incident to change in-load to provide for the application to the second piston area of fluid under pressure which is equal to or less than the regulating prfes- 9. The combination with a machinehaving a iiuid pressure responsive controlling device, ofl

means providing a force dependent upon speed of the machine; means for transforming said force into fluid under regulating pressure and including a movable aggregate; said aggregate comprising a movableabutment subject to said force, biasingmeans acting on the abutment in opposition to said force, and a piston valve abutting saidabutment: means for imparting spinning motion to the piston valve; means including a nrst for applying to the piston valve.

and in opposition to said force, changes in 'reg-- ulating pressure concurrently as they occur;

means including a second piston area for gradually applying to the piston valve, and in the same direction as said force, changes in said regulating pressure; and means for supplying uid under regulating pressure to said device.

10. In a governor for prime movers of the type having an admission valve, means providing a governing pressure varying as an operating characteristic of the prime mover, a transformer providing a regulating iiuid pressure; a device responsive to regulating uid pressure for controlling the admission valve; said transformer including an element movable from a neutral position, in one direction, to increase the regulating pressure, and, in the other direction, to decrease such pressure; first, second and Athird abutment areas for the movable element; the second and'third areas being equal and facing in opposite directions with the first area facing in the same direction as the third area; means for applying fluid under governing pressure to the rst area; biasing means exerting its effect on the movable element in opposition to the governing pressure; means providing first and second pressure chambers for the second and third areas, respectively; means for supplying iiuid under regulating pressure to the first chamber; means providing a passage connecting the first and second chambers, orice means for said passage; and an accumulator communicating with said passage between the orifice means and the second chamber.

11. In a governor for prime movers of the type having an admission valve, means providing a governing pressure varying as an operating characteristic of the prime mover, a transformer providing a regulating fluid pressure; a device responsive to regulating fluid pressure for controlling the admission valve; said transformer including an element movable froma neutral position, in one direction, to increase the regulating pressure, and, in the other direction, to

decrease such pressure; rst, second and third abutment areas for the movable element; the rst and second areas facing in opposite directions and the second area facing in the same direction as the third area; means for applying iiuid under governing pressure to the third area; biasing means exerting its eiect on the movable element in opposition to the governing pressure; means providing first-and second pressure chambers for the rst and second areas; means for supplying fluid under regulating pressureto the rst chamber; passages for connecting the rst and Asecond chambers and for draining the second chamber; orice means for the passage connecting the chambers; an accumulator communicating with the connecting passage between the orice means and the second chamber; and

valve means providing for opening and closing transformed pressure for said supply passage: means for biasing the aggregate to move the control valve in one direction: means for applying said governing force to the aggregate to effect movement of the control valvelin the otherdirection: means providing a pressure chamber closed by a movable pressure abutment operatively connected to the control valve and disposed so that pressure applied thereto provides a force opposing said governing force: accumulator means: passages for connecting said supply source to said pressure chamber and to said supply passage" and for connecting the accumulatormeans to said pressure chamber and to the supply passage: and means including manipulatable valves cooperating with said passages, for standard operation, to isolate the accumulator means and to provide for unrestricted communication of said supply source with the' pressure chamber and with the supply passage; and, for anticipating operation, to provide for restricted orifice communication of said source with the pressure chamber and for unrestricted communication of said source with the supply passage and of the accumulator means with the* pressure chamber.

13. The combination with la machine having a control element, of governing mechanism including means providing a governing force: means operated in response to fiuid pressure to position said control element and including a supply passage: means providing pressure supply and exhaust connections: means for transforming governing force changes into pressure changes and comprising a pressure control valve aggregate including a control valve movable in opposite directions to provide, in cooperation With said connections, a source of fluid under transformed pressure for said supply passage: means for biasing the aggregate to move the control valve in one direction: means for applying said governing force to the aggregate to effect movement of the controlv valve in the other direction: means providing a pressure chamber closed byga movable pressure abutment operatively connected to the control valve and disposed so that pressure applied thereto provides a force opposing said governing force: accumulator means: passages for connecting said supply source to said pressure chamber and to said supply passage and for connecting the accumulatormeans to said pressure chamber and to the supply passage: and means including manipulatable valves cooperating with said passages, for

base load operation, to provide an orifice in the v supply passage restricting flow therealong from the source, for unrestricted communication of said source with the 'pressure chamber, and for communication ofv the accumulator means with said supply passage at the sdevoi' the orifice remote from said source.

14. The combination with a machine having a control'element, of governing mechanism including means providing a governing force: means operated in response to fluid pressure to position said control element and including a supply passage: means providing pressure supply and exhaust connections: means for transforming governing force changes into pressure changes and including a pressure control-valve movable yin opposite directionsto provide, in col operation with said connections, a source of fluid under transformed pressure for said supply passage: means for moving said control valve insages, for standard operation, to isolate the accumulator means' and to provide for unrestricted communication of said supply source with the pressure chamber and with the supply passage; for anticipating operation, to provide for restricted orice communication of ,said source with the pressure chamber and for unrestricted communication of said source with the supply passage and of the accumulator means with the pressure chamber: and,` for-base load operation, to provide an orifice in the supply passagerestricting ow therealong from the source, for unrestricted communication of said source with the pressure chamber; and for communication of the accumulator means with said supply passage at the side of the orifice remote from said source.

15. The 'combination with av machine having a control element, of governing mechanism including means providing a governing force:'

means operated in response to iiuid pressure to position said control element and including a4 supply passage: means providing pressure supply and exhaust connections: means for transforming governing force changes into pressure changes and including a pressure control valve movable in opposite directions to provide, in co operation with said connections, a source of uid under transformed pressure for said supply passage: means for moving said control valve including means providing for application of governing force thereto and means providing first and second pressure chambers closed by first and second movable pressure abutments operatively connected to the control valve, said pressure abutments being arranged in opposed relation and the first-.abutment being so disposed that pressure applied thereto provides a force acting on the control valve which opposes the governing force: accumulator means: passages affording communication of said' source with said first and second chambers and With the supply passage. connecting the accumulator means to said first and secondchambers and to the supply passage and providing for drainage from the second chamber: means including manipulatable valves cooperating with said passages, for standard operation, to isolate the ac-l cumulator means, to drain the second pressure chamber, and to provide for unrestricted communication of the supply source withthe first pressure chamber and with the supply passage: for anticipating operation, to drain the` second pressure chamber, to provide restricted orifice communicationof the source with the rst pressure` chamber, and to provide unrestricted communication of the source withthe supply passage and' of the accumulator means with the pressure chamber; vfor base load operation, to drain the second pressure chamber, to provide an orifice for the supply passage restricting unrestricted communication of the source with the first pressure chamber and of the accumulator means with the supply passage at the side ofthe oriiice remote from said source and, for speed-adjusting operation, to provide for unrestricted communication of the source with the first pressure chamber and with the supply passage, for an orifice between the source and the second pressure chamber, for communication of the accumulator means with the second pressure chamber, and for drainage adjustment of the second chamber to vary the pressure attainable therein as required by the extent of speed adjustment.

16. The combination with a machine having a control element, of governing mechanism including means providing a governing force:

means operated in response to fluid pressure to position said control element and including a supply passage: means providing pressure supply and exhaust connections: means for transforming governing -force changes into pressure changes and including a pressure control valve movable in opposite directions to provide, in cooperationy with said connections, a. source of fluid under transformed pressure for said supply passage: means for moving said control valve-including means providing for application of governing force thereto 'and means providing first and secondpressure chambers closed by first and second movable pressure abutments operatively connected to the control valve, said pressure abutments being arranged in opposed relation and the first abutment being so disposed that pressure applied thereto provides a force acting on the control valve which opposes the governing force: accumulator means: passages affording communication of said source with said first `and second chambers and with the supply pascooperating with said passages, for standard operation, to provide an orifice restricting flow from the source and along the supply passage, to provide unrestricted communication of said source with the first pressure chamber, to provide for communication of the accumulator means with said supply passage at the side of the orifice remote from said source, and to drain said second pressure chamber; and, for speedadjusting operation, to provide for unrestricted communication of the source with thev first chamber and with the supply passage, foran orifice between the source and the second pressure chamber, for communication of the accumulator means with the second pressure chamber. and for drainage adjustment of the secondchamrequired lby the extent of speed adjustment.

n fiow therealong from said source, and to provide 17. 'I'he combination with a machine having a control element, of gouerning mechanism in-l cluding means providing a governing, force: means operated in response to nuidpressure to vposition said control element and including a supplypassage: means providing'pressure supply and exhaust connections: means for transforming governing force changes into -pressure changes and including a pressure control valve movable in opposite directions to'provide, in cooperation with said connections. a source' of duid under transformed pressure for said supply pasaasasai l sage: means for moving said .control valve ina control element, of governing mechanism including means providing for application of governing force thereto and means providing first sure abutments being arranged in opposed relation and the first abutment being so disposed that pressure applied thereto provides a force acting on the control valve which opposes the governing force: accumulator means: passages aording communication of said source with said iirst and second chambers and with the supply passage, connecting the accumulator means to said ilrst and second chambers and to the supply passage and providing for drainage from the second chamber: means including manipulatable valves cooperating with said passages, for anticipating operation, to provide for unrestricted orice communication of said source with the lirst pressure chamber, to provide `for unrestricted communication of said source with the supply passageand of the accumulator means vwith the pressure chamber, and to provide drain- 'age for the second pressure chamber: and, for speed-adjusting operation, to provide for unrestricted communication of the source with the rst chamber and with the supply passage, .for an orice between-the sourceand the second pressure chamber, for communication of the accumulator means with the second pressure chamber, and for drainage adjustment of the second chamber to vary the pressure attainable therein as required by the extent of speed adglustment. Y

18. The combination with a machine having a control element, of governing mechanism including means providing a governing force: means operated in response to fluid pressure to position sage: means providing pressure supply and exhaust connections: means for transforming governing force changes into pressure changes and including a pressure control valve movable in opposite directions to provide, in cooperation with said connections, a source of uid under transformed pressure for said supply passage:

means for moving said control valve including means providing for application of governing' force thereto and means providing iirst and second pressure chambers 'closed by rst and second movable pressure abutments operatively connected to the control valve, Isaid-pressure abutments'being arranged in opposed relation and 55 -the iirst abutmentrbeing so disposed that pres- I 75 19. The combination with a machine having sure applied thereto provides a force acting on the control valve which opposes the -governing chamber: and means including manipulatable.

valves cooperating with said passages, for speedadjusting operation, to provide for unrestricted commlmication of the source with the rst `pressure chamber land with the supply passage, for an. orice between the source and the vsecond pressure chamber, for communication of lthe accumulator means with the second pressure chamber, and for adjustment of drainage from the second pressure chamber as' determined bythe desired speed adjustment. 1

said control element and including a supply pascluding` means providing a governing force: means operated in response to quid pressure to position said control element. and including a supply passage: means providing pressure sup- 5 ply and exhaust connections: means for transforming governing force changes into pressurel changes which are larger than but proportionate to the forcechanges and including a pressure control valve movable in opposite directions to provide, in cooperation with said connections, a source of fluid underA transformed pressure for said supply passage:l means for moving said control valve including means providing for application of governing force thereto and means providing rst and second pressure chambers closed by rst and second movable pressure abutments operatively connected to the control valve, said pressure abutments being arranged in opposed relation and the first abutment being so disposed 20 that pressure applied thereto provides a' force acting on the control valve in opposition to the resultant of the governing and spring force: ac-

cumulator means: passages aii'ording c ommuni-` I cation of said supply source with said first and 25 second chambers and with the -supply passage, connecting the accumulator means to said rst and second chambers and to the supply passage, and providing for drainage from the second pressure chamber: and means including manipulatable valves cooperating-with; said passages, for standard operation, to provide for isolation of the accumulator means, to drain the second pressure chamber, and" to provide for unrestricted communication of said source with the first chamber and with the supply passage; and, for J speed-adjusting operation, to provide for unrestricted communication of said source with the first prsure chamberfand with the supplypassage, to provide an orifice restricting flow vfrom `40 said source tothe second pressure chamber, to provide for communication of the accumulator means with the second pressure chamber, and to provide for drainage adjustment oi the, second chamber to vary the pressure of latter as required A by the etent of speed adjustment.

20. 'I'he combination with a machine having a control element, of governing mechanism including means providing a governing force: means operated in response to iiuid pressure to position said control element and including a supply passage: means providing pressure supply and exhaust connections: `means for transforming governing force changes into pressure changes which are larger than but proportionate to the force changes and including a pressure control valve .movable inopposite directions to provide, in cooperation lwith said connections, a source of iiuid under transformed pressure for said supply passage: means for moving' said control valve in- 60 cluding means providing for application of governing force thereto andmeans providing rst and second pressure chambers closed by first and second pressure abutments operatively connected to the control valve, said pressure abutments being arranged in opposed relation and the iirst pressure abutment being so disposed that pressureV applied thereto provides a force acting on the control valve in opposition tothe resultant of the governing and spring forces: nrst and second accumulators: passages aiording vcom-'- municatio'n of said supply source with saidrst and second chambers and with the supply passage, connecting the iirst accumulator to the first chamber or to the supply passage, connecting the 76 supply passage; for anticipating operation, to

provide for restricted orifice communication of the source with the'rst pressure chamber, vfor unrestricted communication of the source with the supply passage and of the first accumulator with the first pressure chamber, for isolation of the second accumulator and for drainage of the second pressure chamber; for base load op- I eration, to provide an oriiice restricting iiow from said source and along the supply passage, to provide unrestricted communication of the source with the first pressure chamber, to provide for communication of the rst accumulator with the supply passage at the side of the orice remote from the source, and to provide for drainage of the second pressure chamber; and, for speedadjusting operation, to provide for unrestricted communication of the sourcewith the first pressure chamber and with the supply passage, for an orifice restricting flow from the source to the second pressure chamber, and for adjustment of drainage from the second'chamber as determined by the desired speed adjustment.

21. In a governor for primeln'iovers of the type having an admission valve, means providing -a governing force varying as a function of the speed of the prime mover, a transformer responsive to changes in governing force to provide changes in regulating iiuid pressure, a device responsive to said regulating uid pressure for controlling the admission valve, means responsive to speed change incident to load change for modi-'- fying the action of said transformer to control the regulating fiuid pressure provided thereby so that in changing from one load condition to another the prime mover speed at the new load condition is restored to the value it had at the oid load condition, and means for rendering the lastnamed means effective or ineffective.

22. The combination with a prime mover having a valve, of governing mechanism providing a regulating pressure varying as an operating characteristic of the prime mover, a servo-motor including an operating element connected to said valve and a pilot valve for controlling the admission and exhaust of motive fluid to the operating element, `means providing a pressure chamber into which one end of the pilot valve extends, means including an orifice for supplying fluid under pressure to the pressure chamber, means con-trolling the escape of fluid from the pressure chamber including -a bore formed in the pilot valve and an escape-'controlling valve cooperating therewith, a first spring for biasing the pilot valve toward the escape-controlling valve, means for positioning the pilot valve including a second spring andan abutment subject to fluid under regulatingl pressure, and means responsive to movement of the operating element to change the force -of the second spring so as to restore equilibrium of forces acting on the pilot valve with the latter in position for restoration of the pilot valve to neutral position by the force of the first spring and of the pressure in said pressure cham- 'ber and acting on the end of the pilot valve 8l therein.

ANTHONY F. S'CHWENDNER.