US1117699A - Turbine. - Google Patents

Description

A. PEAU.

TURBINE.

APPLICATION FILED 1118.20, 1911.

Patented Nov. 17, 1914,

Imm/ENTER- WITNESEEE'- AT1-:1R Nam VW il Application fled February 20, 1911.

To @ZZ whom may concern f Be it known that i, ARNOLD rDrnU, a citiv zen of the Republic of Switzerland, residing at lriiln'aukee, in the county of Milwaukee and State of ilfisconsim have invented a certain new and useful Improvement in Turbines;` ot' which the following is a specification.

This invention relates to improvements ii the construction of turbines and ticularly to ineens for lmlancin? ners of turbines,

The ohiect ot the invention a means r balancing the ruin i hydraulic, or other tluid pressure tu i which is simple in construction and eine in operirticn.4

Si cler conception ot several embodiments ci the intention can be obtained by reierrinu' to the accoinn nying drawing iu which like reference chan designate the saine or siiniiar parte in d arent views.

Figure l i e transverse vvertical section through a hydrauiic turbine ot the inward flow type. Fig: 2 is en eniargjed fingiucnv tary vertical section o'i' the turbine shown in Fig. l showingconstructive details which here been omitted from the disclosure in Fig. l. Fig. 3 is a similar vien' of e modification.

The snail shell casing l, which receives the water supply frein a suitable penstocli, not shown, incioses the high pressure chamber 2.- Guide ribs 3, which direct the discharge from the high pressure chamber 2 in the usual mannenere cirected tunejeutialiy toward the turbine runner 7 which is mounted on the main turbine shaft running in bearing in annuiar series of guide varies Ll, haring cperating stems G projiecting` iat-ereily therefrom, are inountef to swing intermediate the outer and inner casings Q0, 2i, of the turbine. rhe guide Yanes ainiso directe". tangeniuiiy toward the turbine runner 77 r he discharge of the tur- .oinefrju Y 7; directed toward the drnt'ttubdg i c retrait-tube 9 connects Withthe l i teii-reiieefnot shown, in the usual manner.

The mein ,shiift of the turbine is mounted suitable bearings ozfnhich one bearing 12 is shown, anldli's generaily direct connected i toen electric or lother power generator, not

shownmThe shaftrnsan extension of the tari the thrust bearing i3 there- Serial No. 609,573.

which thrust coliars i7 formed on the shaft S, are adapted to bear. rLillie bearing i3 is adjustable longitudinally ofthe shaft 8 b v means ot shixns 19 inserted between the turbine and bearin?r casings.

The balancing chamber li is torined by the outer casing 20 and the turbine runner T. and annular in form. The balancing chamber lf) is formed by the inn-er turbine casing' 2i and therunner und is also annular in Llorin. The two cl iff), il in the illustrated enibodini tion. unf oi ennui area in nianes 'pe i sha'lt. The annular 'Formed by the outer turbio the turbine runner i'. connects wit; the draft-tube 9 through ilu; nine 151 the ripe i6 beingr controllable by a raifc lit 'Jhr' dial cross ci .ui ci the f uber i actly equai to the cross i or chnrne opening* iii-oni tln ""hine reim r The surfaces on the ci and i-inr-r' cf. ings OO, 2i, between u'hicl ihe guide ren-9. -L coact. Fig. are lined nitl. suitaa'lrrings 2T. Tfearing' rings 20j ai lixed r.- the turbine casing's 20, Qi,`and turbine run ner T, intermediate the chambers 1l, 10. and the chamber l and draft-tube These wearing rings 28, 29, nre oi' equal diameter and of equal urea along adjacent relier' surY faces. TWiththe turbine runner 7 inserted Within the turbine casings L0, Q1, slight annular circumferential spaces 22, 2G, exist bctween the outer peripher;7 oi the runner 7 and the inner surface ot the rings 2?. "nnular radial spaces 03, 25, e' st between the adjacent surfaces oi: Vthe rings 28, 29, on either side of the runner 7, The circumferential spaces 22, 26, ere of substantiaiy constant uxieifiength as the unimi niotion o the 'runner is so sniali as to here substantially no eilt-ect onthis iength. This Sinai?,- ness oi the axial motion' off-the runner 7 can best he appreciated n'lienfit is pointed out that it is less than the mechanical cieerance a t' the thrust h xaring and t uit thiisdnechanical clearance itself is less than the mechanical clearance at the annular spaces'ih. In other Words, on account of the limited play in the mechanical thrust bearing, the runner T is Tprevented from rubbing :it annular spaces Q5; and as soon as the balancing fluid pressures are active, the revolving; parts will even be prevented thereby from c n u ni i rubbing at the mechanical thrust bearing.

-This results in the revolving parts having an exceedingly small end play.

Suitable mechanism for operating the guide vanes 1 is attached to the outer ends of the operating stems 6 of the vanes 4. The operatingring 5 is connected to this mechanism and serves to adjust the vanes 4 to any desired position. AThe details of the operating mechanismfor the guide v anes 4: have been omitted from the present disclosure since they form no part of the present invention and are well known in the art,

Referring to the modification, see Fig. 3, the turbine runner 7 O is inclosed within the outer and inner casings 200, 210. A series of balancing chambers 100, 101, are formed between the inner casing 210 and the runner 70, while a second seriesof balancing chambers 110, 111, exist between the outer casing 200. and the runner 70. Constant sized, annular, restricted passages 220, 260, exist between the outer periphery of the runner 70 and the inner cylindrical surface of the ring4 27. Automatically variable-sized, annular radial passages 230, 250, exist between side surfaces of the runner 70 and casings 210, 200, respectively, and form` means for discharging pressure from the inner chambers 101, 111, respectively. The annular, radial passages or spaces 122, 121, which exist between side surfaces of the runner 70 and casings 210, 200, respectively, form automaticall variable means of pressure communication between the chambers 100, 101, on one side and chambers 110, 111, on the opposite side of the runner 70. u

During the operation of'the turbine, the fluid under pressure which at such time exists within the chamber 2, is admitted to the turbine runner 7 through passages between the guide ribs 3 and guide vanes 4., and after being relieved of its energy inthe runner 7, is discharged to the draft-tube 9 from whence itl flows to the tail-race. As the working fluid passes the annular spaces 22., 26, owing to the high pressure thereof, a portion flows into the annular balancing chambers 10, 11, formed intermediate the casings 21, 20, and the turbine runner 7. The chamberflli being connected through the pipe 16 to the draft-tube 9, has established therein a pressure equal to that within the draft-tube 9. This pressure may be considerably below atmospheric. It will be noted that with Ithis arrangement, and'in the specific embodiment illustrated, on account. of the equal effective areas of the balancing chambers 10, 11, as well as the equal effective areas exposed to the draft-tube pressure, the turbine runner 7 is exposedto exactly equal pressures on either side thereof. If the p'redetermined eifective areas of the balancing chambers 10, ,11, are unequal, the fluid pressure must also be unequal but inversely so in order to equalize the total fluid pressures on opposite sides of the runner 7. These total fiuid pressures must be equal in all cases where there is no additional force on the' runner to be considered, such as weight of revolving parts in a vertical machine. In such case these total fluid pressures are unhequal only to the` extent of the additional force on the runner 7. If, however, for any reason an additional thrust should be thrown upon the runner 7 at one side thereof, thus unbalancing the total end forces on the runner, one of the annular radial spaces 23, 25,

will be diminished.` Because the annular inlet spaces 22, 26;, remain of constant cross section and substantially constant length, this will cause less high pressure Huid to pass through thechoked radial space and build up pressure within that one of the corresponding balancing chambers l0, 11, on

the side. of the restricted passage. More spesure within the chamber 1l places a thrust upon the left face of the runner 7 to bring `same back to normal position by balancing the additional thrust which primarily caused y the shifting of the runner 7 to the left.

It will be seen that if for any reason the runner -7 is forcedtoward the right,vthe

operation of the balancing device will be similar, the annular space 25 in this case increasing and causing the pressure within the balancing chamber 10 to build up while that within the balancing chamber 11 is diminished.

The bearing 13 and thrust members 18 ar;- so adjusted by means of the shims 19 as to permit contactof the thrust collar 17 with 'the thrust members 18 only during starting of the turbine and before pressure has been established withinrthe balancing chambers 10, 11. After the turbine is running normally, the thrust collar'17 will be free lfrom coaction with the thrust members 18. the thrust being automatically .los

balanced by lbevariations in pressure withl within said casing, a pressure chamber at one side of said runner, means of pressure communication to said chamber, said means being ofv constant cross-section and substantially constant length, means of pressure discharge from said chamber, said means comprising spaced opposed relief surfaces of said runner and casing, and balancing means on the opposite side of said runner for urging same in one direction only.

'2. In 'combinatiom a casing, a runner within said casing, pressure chambers on opposite sides of said runner, means of pressure communication to said chambers, said means being of constant cross-section and substantially constant length, and means of pressure discharge from said chambers, said means comprising spaced opposed relief surfaces of said runner and casing.

3.111 combination, a casing, a runner Within said casing, a series of *balancingpressurechambers at one side of said runner, means of pressure communication to said seriesof chambers, said means being of constant cross-section and substantially cornstant length, means of pressure discharge from said series of chambers and of pressure communication between the chambers of said series, said means of discharge and of communication each comprising spaced opposed relief surfaces of said runner and casing, and means for subjecting said runner to a counter-balancing pressure.

In combination, a casing, a runner within said casing, a series of balancing pressure chambers on opposite sides of said runner, means of pressure communication to each of said series of chambers, said means being of constant cross-section and substantially constant length, and means of pressure discharge from each of said series and of pressure communication between the chambers of each of said series, said means of discharge and of communication each comprising spaced opposed relief surfaces of said runner and casing.

In combination, a casing', a runner within said casing, a pressure chamber at each side of said runner, said chambers having annular inlet spaces ot' constant crosssectioual area and substantially constant length and located between cylindrical surfaces of said runner and casing, and said chambers having annularoutlet spaces of variable cross-sectional area.

In testimony whereof, I athx my signature in the presence of two Witnesses.

ARNOLD PFAU. `Witnesses I?. L. PURSE, L. Quinny.'

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