US2910005A

US2910005A - Turbine driven pump

Info

Publication number: US2910005A
Application number: US427599A
Authority: US
Inventors: Pierce T Angell; Cliborn Robert
Original assignee: Thompson Ramo Wooldridge Inc
Current assignee: Northrop Grumman Space and Mission Systems Corp
Priority date: 1954-05-04
Filing date: 1954-05-04
Publication date: 1959-10-27
Anticipated expiration: 1976-10-27

Description

' Mwls Oct. 27, 1959 P. T. ANGELL. Erm.

TURBINE DRIVEN PUMP Filed May 4, 1954 5 Sheets-Sheet 1 B'erce T' A1256!! w F0/be U/jborn 7 2f H5 Oct. 27, 1959 Filed May 4. 1954 P. T. ANGELL. ErAL 2,910,005

TURBINE DRWIVEN PUMP 5 Sheets-Sheet 2 Inra-Tlfn T5 oa. 27, 1959 p. T. ANGELL Em. 2,910,005

v TURBINE DRIVEN PUMP Filed may 4, 1954 s sheets-sheet s Pierce T Ange/ 24 .7? [zeri Cjborfz E: Li l #MH Z L ?E- TURBINE DRIVEN PUMP Pierce T. Angell, Pepper Pike Village, and Robert Cliborn, South Euclid, Ohio, assignors to Thompson Ramo Wooldridge. Inc., a corporation of Ohio Application May `4, 1954, serial No. 427,599

-s claims. (c1. s- 87) Ftentedoct27, 1959 Tice Z rotor in combination with a key extending radially and nonrotatively secured to the shaft carrying said rotor.

.Another feature of the present invention is the provision, of concentric turbine inlet and pump outlet fluid carrying chambers concentrically mounted about bearing means for ar combined turbine and, pump whereinthe extremely strong with ta minimum of weight and a maximum offluid'ow per inch of diameter of the turbine rotor. These requirements are extremely important in the eicient design of modern light weight equipment and have. been considered absolutely necessary in order to utilize the compressed gases available for a power source on modern jet aircraft, for example.

By the present. invention, a simplified and substantially improved turbine rotor structure has been provided while retaining an extremely small turbine rotor diameter and while maintaining the cost of manufacture' at a minimum.

InV reducingthe cost of theV present turbine apparatus, .applicants have simultaneously achieved substantially greatervstrength thereby permitting high operating speeds with a minimum of operational breakdowns. Further, through the use of a novel, compact, nesting arrangement wherebyl the small diameter turbine inlet is positioned in immediate. contact with the high pressure outlet of the associated uid pump, cooling of the bearings of the combined turbine andl pump is effectively provided. Further, cooling of the compressed fluid is provided in situations where the temperature of the compressed fluid reachesy an undesirably high level. Thus, `through the compact design herein disclosed, a highly ecient, yet extremely simpleV turbine and pump structure is provided i rshown in Figure l;

wherein great durability is provided in the rotating structural components and, further, unusually ei`cient cooling is achieved.

It is therefore an object of the present invention to provide a novel combined turbine and pump structure.

Another object of the, present invention is to provide a novel turbine rotor having a novel drive connection to the, turbine output shaft.

Still a further object of the present invention is to provide` a simplified turbinenozzle and rotor construction.

Yet another object of the present invention is to providey a novel interrelated turbine inlet lluid and outlet iluid heat exchanger cooperating with the bearings supporting both the turbine and the pump drive shafts.

Still another object of the present invention is to provide a novel spring retained drive connection for turbine rotors and the like. w

Yet another object is to provide a method of manufacturing turbine nozzle passages in a simplified manner.

A feature of the present invention is the provision of a radially extending key way in the end face of the turbine bearing means supportsthe drive shaft for both said turbine and said pump and is positioned in immediate heat transmitting relationship to both the turbine inlet iluid and the pump outlet uid.

Still a further feature of the present invention is the provision of a simplified two piece pump vand turbine housing in which the pump outlet uid passes in direct contact with the outside of the turbine housing :to effect heat transfer therewith. I

Another object of the present invention is to provide a lturbine having a large ratio of ow area per inch of turbine rotor diameter. 'i

A further object of the, present invention is to provide a novel drive connection between the turbine rotor'and l its supporting shaft whereby radial expansion and, hence, axial contraction of the rotor4 is automatically compensated for and looseness at high rotational speeds thereby eliminated.

Still Vother and further objects and features of the present invention will at once become apparent to those skilled in the art from the'consideration of the attached ,sheets of drawings wherein: s Figure l is an elevational view in cross section of Athe combined turbine and pump of the present invention;

Figure Z- is an end` elevational view of the structure Figure 3` is across-sectional view taken along the line III--III of Figure l; j

Figure 4 is a kpartial elevational view in cross-section showing a modified form of turbine nozzle and' taken along the line similar to IV'.IV of Figure 2;

Figure 5 is a partialend elevational view of the modified` form of nozzle shown in Figure 4;

Figure 6 is a developed view of the blading of the turbine nozzle constructed according tothe embodiment shown in Figures l and 2;

Figure 7 is a developed view of the blading'of the turbine. nozzles of the present invention and constructed in accordance with the embodiment thereof shown in Figures 4- and. 5; and' Figure 8 -is' a cross-sectional view of the turbine rotor drive transmitting key and locking device taken along thelines VIII- VIII of Figure l.

As shown on the drawings: Y The Combined turbine drive and uid pump ofthe pres-'- ent invention is shown in somewhat greater than full size dimensions in Figure l. There, the right hand portion of the apparatus operates as a turbine While the letthaud end of the devicetransforms the work energy supplied by the turbine into a centrifugal pumping action for pressurizing a liquid or gaseous medium such as, for example, gasoline or similar fuel for aircraft. 'y As shown in the figures the assembly comprises a three part housing 10 composed of a central pump housing 11, a pump inlet housing 12 and an air circulating housing 13V provided with an axial air ow controlling 'housing 14; The central khousing 11 is provided with an axially extending bore 15 in which a drive shaft 16 is mounted by means of conventional ball bearings 17 and 18. Axial movement of the shaft 16 is prevented by the shoulders 19 in thebore 15, the metal spacing sleeve 20, the spring retainer 21 andthe abutment wall 22 secured to the housing 11- by means countersunk screws 23. y. The drive shaft 16 carries a turbine rotor Z5-at its right hand, or turbine, end. The rotor 25l is abutted against the thrust abutment 26 and is maintained axially positioned thereagainst by means of the radial key 27 positioned in a diametrical slot 28 in the shaft 16 and maintained in position by means of the threaded nut 29.

As maybe seen from a consideration of Figures l and 2 ,'air enteringthe housing l13 by means'of'the air inlet '1311 passes around the circumference of the air circulation .housing 13 Yand is directed axially' `therefrom through the' nozzle plate 30 by the nozzle vanes 30a as indicated bythe arrows 31.V As may be seen from, Figure 1,` the Vnozzle .plate 30, which wi1l. be more fully discussed "below issecured by screws 32 tothe intermediate support 'member 33 which is inpturn secured to the central housing 1 1 by means ofthe screws 23. The in# termediate support 33 may be integral with or otherwise permanently secured to the innermost portion 13b of the housing'13.or, as an alternative method of manufacture, the support 33 may instead bear a sliding t relationship with the portion 13b at 33a to thereby provide a Huid tight seal. 'Y

In the general arrangement above set out, compressed air introduced in the direction of the arrow shown in Figure 4V2 through the inlet 13a will pass through the nozzle passages 30b and impinge upon the vanes 25a of the turbine rotor 25 thereby rotating the shaft 16 through the key ,27.l The shaft 16 is drivingly connected to the centrifugal pump rotor 35.

y The pump rotor 35 draws low pressure fuel or the like from the inlet 36 and delivers the fuel through centrifugal action `to, the rotoroutlet 37. `From thence it travels axiallythrough the diluser passages 38 to' the collecting ring 39 from whichgthe-fuel is delivered through the The'r'o'tor 35 is maintained in axial and radial alignment by means of the bearing and wear'surfaces 41 and 42 as well as by the bearings 17 and 18. Although the rotor 35 may be secured to the shaft 16 'in a number of pressed gas in the chamber 13. However, it is desired that the temperatures in both chambers or housings 11 and 13 be maintained at a minimum and that the temperature of the bearings 17 and 18 likewise be retained at a minimum value. Therefore, the arrangement shown in the present invention provides a maximum possible attainment of this end by placing the chambers 11 and 13 in heat transfer relationship with each other and with the bearings 17 and 18 whereby the temperature of all three will be maintained at a minimum, average value determined by the coolest of the three elements.

As has been above generally described, the rotor of the turbineis drivingly connected to the shaft 16 by means of a key 27. The key 27 is exceptionally effective in connecting the rotor to the shaft 16 for several reasons. In the first place, as those familiar with the art are aware, high speed rotation of the turbine rotor 25 will cause a slight molecular `movement of the lmetal in a radial direction causing a radial expansion of the rotor. TheY radial expansion of the rotor causes a simultaneous axial contraction as a result ofthe outward displacement of the metal. This radial contraction will, unless compensated, cause an undesirable looseness in the drive connection.l By providing an axially urged key 27 which is constantly maintained against the end of the rotor 25 by means of a heavy spring, no looseness whatever can be interjected into the coupling between the rotor and the drive shaft 16. v

The. spring force urging the key 27 in the axial direction is provided by means of the spring anges 29a on the nut 29., t As maybe se'en from Figure 1, the flange 29a provides an overhanging lpwhich combines with t therecess 29b`to permita deflection of the flange 29a upon the application of a high rotative torque to the ways, one satisfactorycoupling is shown in the drawings.

There, the rotor 35 is splined to the drive member 43 which is in turn keyed axially at 44 to the shaft 16. The rotor 35 ismaintained in its axial position relative to the shaft 16 bymeans of the spacer sleeve 45 which cooperateswith a combinedV abutment and seal 46 to maintain the rotor 35 a xed distance from the abutment 47 on the left hand end of the shaft 16.

-Pressure from the pump rotor outlet 37 may leak into the cavity48 and this leakage is prevented from passing through the bore 15 by means ofthe seal plate 46 which cooperates with the Vspring biased rwipers 49 and 50. While this arrangementhas proven very effective in preventing leakage of the pressurized uid medium,lit is to be understood that otherv types of seals may be utilized if desired without departingn rom the scope of the present invention. i

As may be seen from avconsideration of Figure l, the pressurized fluid entering thecollectng ringr39Y from the pump rotor 35 may circulate past the radial reenforcing ribs' 51-into the portion of the collecting ring 39 imme'. jdiately within the innerwall13b of the housingf13. Thus,`the compressed uid circulates in heat transfer relationship with the incoming compressedair within the turbine inlet housing 13.V Likewise, the' iluid from the pump rotor 35 is also in heat transfer relationship with the bearings 17 and 18 which are tixedly mounted within the bore 15. It will be apparent, therefore, that when the bearings 17 and 18 develop excessive heat, heat will be dissipated to the compressed iluid in the collecting nut 29. Thus, when the nut 29 is tightened down against the key 27, the ange 29a is deected and a resilient set is provided therein. When during operation the rotor 25 contracts axially, the ange 29a will move axially with the key 27 to maintain the key in tight engagement with the rotor 25, and the rotor itself in tight engagement 4with the abutment plate 26 thereby providing a constant, extremely tight, connection.

. In Vthe second place, an extremely eflicient coupling is provided through the use of the radial key 27 since the strength of the hub of the rotor 25 is increased through the lelimination of axially extending spline grooves of the conventional type. AV very small hub may be provided in the rotor 25 when a key of the type shown at 2,7 is Vutilized since the ,machiningl of a diametrical slot for the key 27 does not materially affect the radial bursting strengthv of the hub. This is an improvement over the conventional type of'splne coupling wherein the splines act as` notches in the effective diameter of the hub and `greatly reduce itsbursting strength.: Jlt should be remembered that the axially extendngsplines of a conventional connection not only detract from the strength of the hub through a reduction in the metal, and hence the .effec- 1 tive thickness of the hub, butalso provide a notch elect Vterial only. Q

ring 39, as well as to the' compressed gas within the causing a localization of the stresses at the'minimum radial thicknessI of the hub. This concentration of stress causes a serious weakening of the hub, which is substantially in excess of the weakening effect of the removal of ma- The apparatus ofthe present invention includes an Vextremely simple turbine nozzle and vane construction. Through the useof ,a small diameter hub, as above described, short rotor vanes 25a, which vanes extend axially relatively a great distance, may be provided. By means 'f .thi'svconstructiom la 'minimumniunber of turbine 'buckets'may be' provided thereby providing a large flow area. This permits the development of'a "considerable amount of power compared to Vlargerdiameter turbines j in.which a 'greater percentage of the-air passageway must of necessity comprise vane structure.- v Y Simplified maxrufacture` of the nozzle and rotor of t the turbine is provided through the provision of. the exhaust housing 14 as a combined 'shroud for the rotor and shroud forv the nozzle blades. As may be seen fronta consideration of Figure 1, the housing 14 provides an outer peripheral confining surface for the air throughout its llow through the nozzle openings 3G as well as 'its diffusion in the turbine blading 25a. VThrough this arrangement, a simple, single, outer shroud element f4 is permitted. Further, the elimination of the need of any outer shroud for either the rotor 25 or the nozzle structure 30 permits the manufacture of both the rotor and the nozzle by means of conventional milling cutters. Thus, the blading 30a of the nozzle blade 3f) may be manufactured by indexing the blade 30 on a conventional milling machine and moving the milling cutter in a direction of the arrow 55 shown in Figure l relative to the plate 30. Movement of the milling cutter along the line indicated by the arrow 55 will automatically cause a converging nozzle passage 30h to be cut into the plate 3G.

The above method of manufacture is extremely simple and, further, may be utilized with only a slight modi-.

iication to provide a nozzle capable of supersonic operation. Thus, as may be seen from a consideration of Figures 4 and 7, a nozzle plate 60 may be provided with converging-diverging nozzle passageways 60a by setting up the milling machine as above described and passing the milling cutter along a helical path shown by the arrow 66 in Figures 4 and 7, and then tilting the nozzle plate 60 in the opposite direction about its central axis relative to the longitudinal axis lovand passing the milling cutter along a helical path indicated by the arrows 67 in Figures 4 and 7.

This two step milling operation provides a converging nozzle passageway in the direction of the arrow 66 until the minimum area neck 68 is reached, at which time the passage begins to diverge. Since, as is well known in the art, a continuous flow passage which is to excelerate the velocity of a gas from an initial sub-sonic value to -a supersonic value must comprise a convergent nozzle passage followed by a diverging section, it will be apparent that the nozzle passageways manufactured as above described, will operate suitably to provide supersonic flow entering the turbine wheel l5, thus providing extremely high speed, as well as eicient, operation. Likewise, as is well known, the provision of a continuously converging nozzle passageway as shown in Figure l will provide an increasing velocity of the gas reaching a maximum of the 'speed of sound as it leaves the nozzle passages and enters the rotor l5.

From the above discussion, it will be apparent that the nozzle plates constructed according to the present invention may very simply be manufactured through the use of conventional milling machines rather than extremely complex machinery ordinarily used for the manufacture of nozzle passageways. This permits extremely inexpensive construction, and in many cases even more important, permits manufacture of such pump and turbine structures by manufacturing concerns not having the complex machinery ordinarily associated with manufacture of turbine nozzle and other complex turbine blade forms. This simplified blading, when taken with the remainder of the very compact structure provides an unusually simple and thermodynamically superior pump and turbine structure capable of eicient use where compactness, efficient cooling and simplicity are required.

It will be apparent to those skilled in the art that we have provided a novel and unusually efficient pump and turbine. It will be understood that various modifications may be made in the structure above set out without departing from the novel concepts of the present invention and we do not, therefore, desire to be limited other than by the scope of the appended claims.

We claim as our invention:

l. A combined turbine and pump comprising a turbine having an annular turbine supply chamber for delivering a compressed fluid axially to a turbine rotor, means introducing Va compressediluid to saidV supply chamber, a pump having an annular collection chamber with a lateral outlet therein for delivering a second pressurized fluid to the lateral pump outlet, sealing means preventing an intermixture of the two fluids, and a shaft rigidly connecting said turbine and said pump for simultaneous rotation, vsaid shaft being rotatably mounted within and concentric to said supply chamber and to said collection chamber and said collection chamber'beingy concentric with" and at least 'i partially telescoped within said supply chamber and in heat transfer relation therewith.

2. A` combined turbine and pump comprising a turbine having an annular turbine supply chamber for delivering a compressed fluid axially to a turbine rotor, means intro-ducing compressed fluid to said supply chamber, a pump having an annular collection chamber with a lateral outlet therein for delivering a second pressurized fluid to the lateral outlet, sealing means preventing an intermixture of the two fluids, a shaft rigidly connecting at its opposite ends said turbine rotor and said pump for simultaneous rotation, bearing means for said shaft, said bearing means being supported within and in heat transferring relation to said collection chamber, said shaft being rotatably mounted within and concentric to said supply chamber and said collection chamber, said chambers being telescoped and in heat transfer relation with each other and said bearing means.

3. A combined turbine and pump comprising a turbine having an annular turbine supply chamber for delivering a compressed uid axially to a turbine rotor, means introducing compressed fluid to said supply chamber, a pump having an annular collection chamber with a lateral outlet therein for delivering a second pressurized fluid to the lateral outlet, sealing means preventing an intermixture of the vtwo fluids, a shaft rigidly connecting at its opposite ends said turbine and said pump for simultaneous rotation bearing means for said shaft, said shaft being rotatably mounted within said bearing means within and concentric to said supply chamber and said collection chamber, said bearing means being supported within and in heat transferring relation to said collection chamber, and said collection chamber being concentric with and at least partially telescoped within said supply chamber and in heat transfer relation therewith.

4. A combined turbine and pump comprising a turbine having an annular turbine supply chamber for delivering a compressed fluid axially to a turbine rotor, means introducing compressed fluid to -said supply chamber, a pump having an annular collection chamber with a lateral outlet therein for delivering a second pressurized iiuid to the lateral outlet, sealing means preventing an intermixture of the two fluids, a shaft rigidly connecting said turbine and said pump for simultaneous rotation, bearing means for said shaft, said shaft being mounted within a concentric to said supply chamber and said collection chamber, said bearing means being supported within and in heat transferring relation to said collection chamber and said supply chamber, and said collection chamber being concentric with and at least partially telescoped within said supply chamber and in heat transfer relation therewith, said lateral outlet being axially spaced from opposite ends of the collection chamber.

5. A combined turbine and pump comprising a turbine having an annular turbine supply chamber for delivering a compressed fluid axially through a nozzle plate to a turbine rotor, means introducing compressed fluid to said supply chamber, a pump having an annular collection chamber with a lateral outlet therein for delivering a second pressurized fluid to the lateral outlet, sealing means preventing an intermixture of the two fluids, and a shaft rigidly connecting said turbine and said pump for simultaneous rotation, bearing means for said References Cited in the le of this patent UNITED STATES PATENTS Schellens Aug. 6, 1929 Schleyer June 16, 1931 8 Bigelow Ian. 17, 1933 Buchi May 23, 1939 Browne July 11, 1939 Schutte Dec. 19, 1939 Larrecq Aug. 27, 1946 Clegern Mar. 29, 1949 Davis4 Dec. 18, 1951 Musikant June 10, 1952 Aue July 8, 1952 Coding Oct. 14, 1952 Wheatley et a1. June 2, 1953 .nah