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NASA AVRADCOM '

Technical Memorandum 83389 Technical Report 83-C-3.-

--' [NASA-'IM-833flg) NASA 'I_RANfM_.53FIfi _ EF.ql_AI_Clt N_:-2qfiSfl: AND l'rS [ROEAELF FFtiCT.q (1_ bltllC([ll_P

_RANSHISE/.C, DES/GN {NA._A) _HC AO2/HF AC! CSC[ 01/_ Ilzzcla_

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' NASA Transmission Research and Its

P b bl Effect Heli pte...._ • ro a e s on co rz Transmission Design

°.*

_-_ Erwin V. Zaretsky• Lewis Research Center

!, Cleveland, Ohio

and

--= John J. CoyPropulsion LaboratoryAVRADCOM Research and Technology Laboratories

_ Lewis Research Center- Cievelund, Ohio

= and

Dennis P. TownsendLewis Research Center

• Cleveland, Ohio

b

Prepared for the- , Thirty-ninth Annual Forum of the American Helicopter Society

.... St. I,ouis, Missouri, May 9-11, 19_3

_ _ _

1983016587

https://ntrs.nasa.gov/search.jsp?R=19830016587 2020-02-19T03:24:39+00:00Z

J

INA!,ATRAN'_MISSIhNRfSFAk,C. ANtiITS PH')FIA_LEJF_LI.]!, ORIGINALPACZ i_ f

ON HELICOPTER TRANSMISSIONDESIGN OF pOOR QUALITY[rwtn V. /ar_t..ky..John .). Coy*. and Dennis P. T()wn_end

,,: National Aeronautics and _pace Administration

i_ Lewis Research Center

Cleveland, Ohio 44]35

-_!, ^bstract is required tO eStahll_h the valid}ix of _naIy',_,,i.',, and computer Codes devel()lmd to predict th_ p.r-'_' tiArAtransmissionresearc==_s oriented tither formance, efficiency, life, and re_lat_llityol

,'-"" t(_advance the state-of-the-art ir mecha.ical power transmission systems.-":_ t_ansfer technology or to add to the fundamental):i body of knowieJqe 6eionging to bearing_t gears, Relatively new concept_ may be required %0

_" lgbr_catian,rolling=element fatigu% life pre- achievesignificant technological advancec. NARAP:;I_'' '_= diction, &ra¢tion phenomena, and mechanlcal_po*er, transmissions studied for application to hellcop_L,,,L _ transfer, Transmissionsstugied for application tars in addition tO the more conventional grafts;

i'_i_ to helicopters in addition to the more conventional transmissions includehybrid (tractlon/gear)L_J,i _; geareg transm_sslonsinclude hybrid (traction/ bearing_ess planetary [3], and split torque trans-__ gear), bearlngless planetary, and split torque missions [4].:'::_ transmissions, Research is being perfor_d tO es-

tablish the validity of analysis and computer codes The NASALewis Research Center in cooperation_ OevelopeO to predict the performance, efficiency, with the U.$. Army Aviation Research anO Develgp-i life, and reliabilityof these transmissions. Re- ment Command's Propulsion Laboratory devlsed a com-

sults of this research should provide the transmis- prehensive helicopter transmission technology re-

s$on designer with analytical tools to design for search program beginning October 19?2 [1]. Tn}sminimum weight and noise with maximum life and el- paper reviews the results of this research ar_3its

i flciency. In adOitiofl, the advantages and limita- probable effects on helicopter transmission oes_gn.tions of new and novel drive systems as well as the

' more conventional systems will be defined. Gears

ii- Introduction Life and Reliability

The helicopter,more than any other contempor- A reliability model for the compound planetaryi_ dry aerospace or industrial _nnovation,has placed gear train (Fig. I) has been derived for use in the

severe performancedemands on power transmission probabilistic design of this type of transmissior,_,,_. components such as bearings and gears. Well- [5,6]. This gear train has the ring gear fixed,

_': gesigned mechanicalcomponents, good materials, and the sun gear as input, and the planet,carrier as'.i'i;i_, lubrication systems which are i.tegrated into he]- output. The input and output shafts are assumed_:!i. Icopterdrive train systems can make the difference to be coaxial with the applled torques and each_ ':ii between a helicopter's reliable, economic operation other; no side or moment loading is (:onsiOereo.

and failure.The reliability model is based on the relic-

/: It has long been a requirement to provide bility models of the bearing [7,8] and gear mesh: technology to detain IOng-llfe, efficient, light- components [g-Ill which are two dimensional Weibull

weight, and compact mechanical power transmissions distributions of reliability as a function of life.that are also low-cost and quiet for both commer- The transmtsston's 90-percent rellability life andcial and military helicopter applications, In gen- basic dynamic capacity are presented in terms of

,;I eral, current state-of-the-art transmission systems input sun rotations and torque (Fig. 2), Due toare disturbingly noisy to the pilot and passengers, the different Wetbull distributions for the bearingThe maintenance rate on these transmission systems and gearing components, the Weibuli model for theis high. The time between overhaul (TBO) and mean planetary transmission is an approximate model.time between failures (MTBF) on present-day helt- This model includes the transmisstofl's 90-percentcopters is much lower than that required for eco- reliability life, Weibull exponent, basic dynamicnomical commercial operation. The helicopter drive capacity, and load-life exponent. The life an_system is generally heavier than desired [I]. reliability model allows the designer to obtain

both qualitative and quantitative c_arisons be-The rellizationof technological improvements tween transmissiondesigns and appli,:ations. For

for future helicopter drive systems can only be oh- an example, the analysis shows that due to the na-talned through advanced research and development, ture of the component life distrlhutions, reducingHence, NASA transmissionresearch is oriented the loading in the transmission make_ the bearingseither to advance the state-of-the-art in mechant- more important _n the life characteristics of thecal power transfer technology or to add to the transmission, |nc_el$ing the |oldfnQ makes the sunfundamental body of knowledge belongin 9 to uear- gear life more (m)oetant(n the over_ii tile dtt=ings, gears, lubrication, Potting-element fatigue, tribution of the t_ansmission, |n a_#!t_on, Seeinglife predictto% traction phenomena, and mechanical a fourth planet gear more than doubles the life ofpower transfer [_]. A considerable amount of work the transmission [6].

*Proput_inn lahorat .... , AVRADCOM Research andTechnnlqqyLahoratori_s,_wi_ Research Center,Cleveland,Ohio.

1983016587-TSA03

ORIGINAL PAG£ lIOF POOR QUALITY

ity, face width, pitch-line-velocity, .ind load ef-S_p_HrGearDesign ficiency.

The design procedure, for designing gear setsas Shown in Figs. 3 and 4 so they will have a min- Fig. 7 shows the effect of given .:ear dzam-imumcenter distance was developed [12,13]. A eter, tooth number, and pltch-Iine-vel_city onminimum center distance design wi11 he lighter _ffictency at a given load. Th)s modet_t_ t(J heavweight, which tS critical in aircraft applications, iiy loaded gear set is most efficient etth fine-Another advantage is that smaller gears will have pitched, large diameter qears operati,q at highless noise due to the smaller pitch line ve]oci- pitch-I|ne velocities. With this method th_ gearties. designer can now desig, a gParset for optimum ef-

ficiency at any operating condition desired.

The derivation of the design procedure iden-tified a two-dimensional design space whose coor- Fig. 8 shows the predicted power tos_ fordinates are number of teeth and dtametra] pitch, three gears designed for the same application.Constraint boundaries for pitting t scoring, and Gear L is a standard gear while K and I_ are bothbending fattgue faituree as welt as the geometric high contact ratio gears, but of difference size.constraint of involute interference were identified From the anslysis based on gear desigr K. it i_

as Shown in Fig. 5. The region of acceptable de- possible to design a high contact ra['o gearsetsign choices is labelled in the upper left of the with an efficiency comparable to a standard geardesign space. Lines of constant slope throcgh the design.origin represent the locus of points in the designspace for which the center distance ts constant. The finite element method is of_,m used to doThe slope of the line represeflts center distance; stress and deflection analysis of gears. A ma3orthe smaller the slope, the smaller tibe center dis- difficulty in the use of the FEMpro_'ams is _iz_n_tance. The minimum sized gear design would then the grid spacing in the reqion of the load. Thebe a gear with dtametral pitch and number of teeth effect of Hertzian deformation contrioutes up towhich correspond to point A on the plot. 20 percent to the total deflection at the gear con-

tact point. Research is reported in [16] that te-A design approach sometimes found in gear lares to choosing the FEH grid for th;s type of

handbooks is to use the interference limit and the problem, in order to properly account for Hertziantooth bending strength limit to define the "best" deflections.design. This gives point B in the design space.Thispoint will giv_ a smaller gear set than point In [I7] a study of the effect of rim thicknessA but it is not a balanced design since it ignores and fillet radius on gear stresses is reported.the pitting and scoring problems that will be en- It was found that compressive stresse_ opposite thecountered in service, loading side of the tooth are most se,lsitive to rim

thickness. Partially supported rtm G)ars SUChasThe procedure was expanded to include the el- tn ltghtwe!ght aircraft tppltcattons'have a de- :i

feet of nonstandard unequal addenda gearing shown crease in the stress with increase to, rim tn_ck- !in Fig. 6 [14], Unequat addenda gearing makes it ness, whereas for fully supported rim gears, thepossfble to r, '_e the size (number of teeth) for opposite ts true. The root stresses increosed w_tnthe same Patio ,_ standard gears without running decreasing fillet radiuS.into kinematic interference. Unequal addenda gear-ing ts Shown in Fig. 6. D_namic Analysis

C;)nventional practice holds that unequal ad- A high contact ratio gear oynan_ic analysi_ _]_dendum geometry is better than standard geometry developed to determine the dynamic i_ads, stresse_,because the short addendum pinion teeth are and deflections for spur gears [18]. The analysisstronger in bending fatigue than the smaller stand- determines the effect on the gear tz;th dynamicsard teeth. The research results show that for with various tooth profile modifications, toothminimum center distance gear sets (which meet the spacing errors, system mass, and system damping.design limits on strength and kinematic interfer-ence) there is no appreciable slze reduction. The The anatys_s was first developeu for internalresults apply in general, since b,ometric similar- and external high contact ratio and _.tandard spurity and strength similitude are maintained for the gears [19]. The aralysis was expanded to includedimensionless result. The critical factor in stz- multiple gear meshes and planetary g!_ars w_th uptng is the Hertzian contact stress, to 20 planets [20]. A computer cod,' was developed

that determines the gear dynamic loads, stresses,This research clarifies the main attributes 1_ _ef|_¢tt_ns. The code plots the results for

_f l_ng and shoot addendum9airing _nd extends w_rk both single tooth mesh and several t_C_h in ser_eson minimum center distance gearin 9, to show the effect Of tooth Spae_n9 ,_eror5. The

program is being expanded to include helical gears°

A eomprehenstvemethod was developed for thedesign of spur gears with improved efficiency over Spiral Bevel Gear Designthe full ran9e of 9ear operating conditions [t_].

• Previously avaitablemethods were 1_ended to pro- The surface geometr_ of circular cut spiralvide an estimate of only full toad efficiency. The bevel gears w_s developed [2i_]. Earlier worknew method w_s then utilized to show the effects was done for the *i_eal" case of a :ogarithmi( ._of spur gear size, pitch, ratio, lubricant viscos- spiral shaped involute tooth [23]. The work is

2

1983016587-TSA04

"-- complimentary to the earlier w_}rk in that iL ad- than or qreal(.r tharl the pltJh llf,_ velocity, il_dresses the problem of (ircular cut spiral bevel addlt Ion, tile pinl(m may h(, c(Jmplet_.ly ip|,,sr,q Atyears whith ire pro(tirol to make on existing pro- jet vel(JLllles that ar_. much lower ()r murh r|,gtler'duction ma.;ntnes, titan the, pltch-line wlc)_ Ity. lhese ael.nlyse- aI

low% the de,stuffer t() h. ate the ()ii jet,, and uptlThe emphasis on the tooth surfa(e analysis i5 m1_e lubr_calionflow and v(_lum,,lur maximum eftl-

on determintn_jthe principal ra_;i_of curvature of ctency and, hence, lower heat generat}u0,.the surface, ln_,pr}nclpal radii, which are tht_maximum and minimum radii at the point of contact An anal_sls and cof!iput__rpro!_rdmca11_ IIL_,GLbetween mating gear teeth are needed to calculate were developed to predict tfl_ variati(m._ _t ,ly,lam_ccontact stress, tOOth contact patterns _hOWll in load, surface temperature, and I-brlcant (el_stOhy-Fig, 9, and tot,elastohydrodyn_uniclubricant lilm drodynamic) film Lhtckn_'_'_ai(mg the c()nta_:t_n,ithickness. ]he formulae and procedures are go,oral path during the enrjagemer_tnt a palr (if_r_v(_lut,and well suited to use In computer algorithms and spur qears [2g]. The analys_ of dyr,an,i_ lo_d :r,-specific results are easily obtained by sympoltc eludes the effect of gear Inertia.,the,effect (ifmanipulativecomputer programs. The work speclfi- load sharing of adjacent teeth, aridth_ _ffe(t (_frally considers involute, straight, and hyperbolic variable tooth stiffnesses which are ob_air_edby acutter profiles. The resultsmay be used _n anal- finite-element method. _esults obtai_,; iron,ysis of gear sets such as in the input stage of TELSGE for the dynamic load distribution5 al(}rvjth-helicoptermain rotor gearboxes and tail rotor contacting path for variuus spe_ds o1 a pair ofgearboxes, test gears show high loads r_(.drthe pit,h IIr,(.

where pitting failures are observed exp,.rlmuntally.Further work was performed to describe spiral Effects of damping ratio, cat,tactrat_,.,tip re-

bevel gear sets with two different mesh contact lief, and tooth error on the (_yr,amic h,_d can bepatterns [24], Two different methods give tooth examined. A lubricant f11m tn_ckness analysis for

_: contact paths _n different directions. One path the 011-58transmission sun-p_nlon gear ,,et_s shown

_.. is across the profile direction of the tooth, the in Fig,,11.other is along the length of the tooth. Each con-tact path offers certaln advantages for increased Gear No_se

_.. life, better lubrication,and reduced _oise and

L:- vibration. The mettlodsdescribed in [,4] indicate Gear noise in he1_copter transmis _on,;_ aI:-_: approaches to take in further analysis of the im- maj()rcontributor to the overall noise _nsIO,.the

plications of two different geometries. Passenger areas of most helicopters. Gear noise isa d_rect resutt of the deviations in th,?gear toot.ll

Gear Materials profiles from the.true involute form (r_rin thegeneralized case, the true conjugate form). It is

Several gear materials have bePr_evaluated for d matter of necessity that the qear prattle be aieodurance life on the NASA LeRC Spur Gear Fatigue tered from the ideal (e ath.mat_(!ally}_)njuqateTester [25]. A colrlparisonof the life of various form. This is to provide a cumpensati,,,,t_ffecttr_gear materials is sbowr_in Fig. IC. The Vasco X-2 a11ow for deflections in the gear support and the'has a life statistlcallyequlvalent to AISI 9310 gear teeth themselves which are caused by th('nor-but has less fracture toughness. The C(d5600 mate- realoperating loads. The e(,senceof n_ise mhlimi-r_al is somewhat better than AISI 9310 but also has zatJon is to balance the noise producv_,:nerlativeless fracture toughness. The best material tested effects of nonconlugacy with the positive effects

:; to date is the EX-53 material which has twice the of desensitizing the gear syst,.,nto th,_effeLt5 _)tlife of AISI 9310 and an equivalent fracture tough- defle(;tiohswhich can cause g(_arml_ali_nmer_tsand

[._, ness. Shot peening of AISI 9310 qears gave a life eccentricities. It is clear that extensive syste_,r_._ improvement of 60 percent over the standard gears modelling of the gear tooth action, pea" Suoport_,, without shot peening [26]. This improvement in stiffnesses, and dynamiL behavior IS requirer,)n

:: life is attributed tO the subsurface compressive order t_ design gears with the appropri.ltenoise_:- residual stress induced by shot peening, compensating tooth profiles.

_ Gear Lubricattor, One 5u_h approach ha5 been complek0_d[Jhj. Atransfer function m_thud for predicting the dynan_lc

_ An analysis for into mesh o11 jet lubrication responses of gear systems with several fr_eshe_wa_: was performed with an arbitrary offset and inclina- developed. The model was applied to the NASA spur

tton angle from the pitch point for the cases when gear fatigue test apparatus, An opttmu_ profile:_. = the oil Jet velocities are less than, equal to, or modification design fnethod was developed and ap-

greater than gear pitch line velocity [27,_B]. plied to the NASA gear rt9, The_profi!L= modlfica:- Equations were developed for m;nlmum and maximum tton c_art ts shown in f_g. 12. The NASA te_t gear

:_ ; (optimum) oil jet Impingement depths. The analysis _t ihown in Fig. 13. N(iise tests and fatigue testsincludes the minimum oil _et velocity required t(i to evaluate the performance of the mtnI_e,umnoiseimpingeon the gear or pinion and the optimum all design wit| begin in the near future.

:_ Jet velocity required to obtain the maximum Im-:_ p_ngement depth, The best lubrication and cooling Measurement Of the_ n()tSe with conventlm_al mi-

_:- is obtained w]th maximum impingementdepth when the croph((nest(}measure _uund pressure le_l_ n_ d_f_:- oil jet v_!o(_ity equa;_ the qear pitch 11,ne velo_ ftcult for most qear_n_ installations be_(au'_e of

city. Less than optimum qear lubrication and C_}ul_ the reverberant conditions of the room _urto.hdingtng is obtained at at| jet velocities that are le.cs the q_ar Installatio(is. Greater sucres "_car, he ix- "q

3

1983016587-TSA05

ORIGIN_,L PACC _OF POOR QUALITY

parted from measurements obtained via accelerome- speed conditions anticipated In art advanLed h_ll-tars mounted on the gearbox housing. However, the copter transmission. The ct)nd|tiofl_ ()i the. te_t,oeffect of the radlatiu;, mechanism that transfers (100 percent power) were a shaft speeU of 3b,OO(svibrations into sound pressure levels Is neglected, rpm (1.3 million DN), a thrust load of lh_ p[Jur,t_

(104l N), and I radial load of 723 pou._ (_;'16 hJ.A method that circumvents this problem has (DN is a speed parameter equal to the h,)re of the

b,en developed [3|]° The method is based on the bearing in millimeters multiplied by the shaftmeasurement of acoustic intensity by tw_ closely speed in revolutions per minute.) The romp,tarspaced microphones. A robotic acoustic Intensity analysis accounted for thermal ai_d merhanlcal In-measurement system (RAINS) was designed and con- teractiQn_ Qf the bearings and their environment.str_¢¢eq to aUtomat_ the ana]y_ of _o_nd fie|d_ The predicted life of thq _eleete_ 33 mmPor_$_rQund_ng gearboxes tn aCtUal _nstal|etions tapered-roller be#ring _t 60 peree_t worated to_d(Fig. 14). Ihe acoustic intensity measurement conditions WaS _n excess of the desired 2500 hours,method does not depend on hov_n9 _n ene¢hOi¢ ¢ham=bar around the 9earbo_ e_d may be use_ _n tht: re- The design and lubrication of large bore (4.7bverberant, multt_ource noise environment found in in.) tapered-roller bearings for operai.ion ata typical test cetl. The RAIMS system will be used speeds up to 2,4 million DN under combined radialSn th_ NASAhelicopter transmission test cells and and thrust loads has been demonstr_teO [35-3?].in the NASAspur gear test rig for the minimum The bearing design was computer OPtlm_;:ed for hi,h-noise gears, speed operation, Lubricant was suppli.:d to the

bearing througP the shaft and directly to both theNoise is related to the kinematic precision of large end and the small end of the rollers.

gear trains. A theory for the kinematic precisionof gear trains was developed [32,33_. The kinema- The advanced high-sPeed bearing r,m with lesstic accuracy defines the actual ratio of input heat generation end ran cooler than'the basel_n,:speed to output speed for every instant in time bearing to which tt was compared aS sh,_wn 1_1fl 9,(fig. 15). The small deviations from the _deal or 18. ]t also was capable of higher sp,ed operatiur_;steady rat_o are the source of high noise levels 20,000 rpm as opposed tu tn_ 15,000 rp,r limit or,and large dynamic loads, the baseline design bearing. Four of the advanced

design bearings made of CflS-lO(JOt4mate'_al ran toThe theory defines kinematic accuracy as _ _4 times rated catalog life without failure.

function of m_chine settings useO in the gear grind-_ng process and as a function of gear eccentricity The high-speed bearing wa_ designed for Iowt,rand deflections. There are two principles that are stress and heat generation _n the critical contactused tO _erlve the theory. The first is that the of the roller large end and the cone rib, Thevector surface normals of the gear teeth must coin_ baseline bearing was only modified to supply lubri-cide, and the second is that t_e vector velocity cant to this critical contact.of the contact point on each gear tooth must coin-ride (Fig. 16). Predictions by the computer program CY_EAN,

for cylindrical roller bearing analys_!,_ have been

Rollin_-ElementBearings verified with experimental data [38,3g]. The ex-perimental verification was conducted with 11_-.,n

The input pinion of main helicopter transmis- bore cylindrical roller bearings at spreds up toside is typically supported on s_acks of _ngu!_r 25,500 rpm. Calculated bearing temperature_ and¢ontact ball bearings or combinations of b_tt arid heat generation agree very well with the experlmen-cylindrical Poller 6earings (Fig. 17). The use of tel data. The program also calculates roller dy-tapered-rollerbearings for th_s application should namics and bearing l_fe considerin9 lubricationandeliminate the problems of load sharing and lubrica- thermal effects. CYBEANis a valuable toot for theLion associated with stacked bearing assemblies. _esig_ an# #n_tysis of cylindrical re!let bearingsAdditionally, tapered-rotter bearings are ideally for difficult end critical appli¢atier-;.suttee for the large enmb_ned _aeiat and thrUStloads from the input bevel p_nton. Spherical roller bearing analysis pred_ction_

by computer program SPHERBEAN have be_ verified

Speed limitations on standard tapered-roller by experimental data [40]. The program calculate_bearings demand that Suitable m_dificattons and roller dynamics, heat g_neration, temperature, andcareful lubricationbe applied for successful oper- bearing llfe. It has capability to Simulate per-alien in high-speed pinion applications in this formance of a planet bearing in planetary gearprogram, the performance of commercially available systems.tapered-roller bearings, medifted for high-speedoperation, was verified both analytically and ex- Experimental verification was conducted withperimentally. The bearing design and the arrange- 40-mmbore, double-rOw, SpheeiCat Poller bear_hO_mpnt of the pinion shaft were selected by computer at speeds up to lg,OOO rpm. Predtctec temperaturesanalysis. The bearing selection was verified ex- Correlated well with e_p_rimental measurements.pertmentallyand an optimum lubricationsystem and Predicted trends in temperaturewith L_arlnq geumflow rates were determined [34J. etry changes were consistent with e_Re:r_mentat ob-

servations.The experimental activity established that

automotive pinion q_ality tapered-roller bearings The usefulness of SPHIRBEANwas demonstratedare capable of reliable operation under load and by its abtltt_ to accurately simulate spherical ._

4

1983016587-TSA06

On,r J

O_ ,_

r.ller b_aring performance in conventl_mal and six of the I_hrlcanLs were t_.stecl If= th, NA',A cje,=rhlgh-spe,,d ranges. [tie program can artist In the fatigue tester to determine the. rile( I .i th,".a' ludeslqn and analysts of spherical roller bearings brl_ants un gear life. llg. 75 shows tt,r re_.lL'_f.r difficult applications such aS tile planetary of these tests. Am.ng the II different lul_r=¢anl,,',tag_ of a hal;copter main transmission or In the efficiency ranged fra_m 9_1.'1 to 9fI.H per(.ni.geared fan or turboprgp Speed reduction units, which is a _{J-percent variation relat ivr t. thr

losses associated with thr mall|rod=l=of ill l_ri¢ y ==idalran_misiton_, toted. Of the sl_. lubricants shclwn ill li(_. LL,.

there was nn correlation between effl(lency andlransmlsslon Evaluation life. The, lubricants h,4d n() ,,igniflcah' (.tiect i_fl............... the vibration signature of ti,.transml',_,lcm. Ad

The data in the* open llteraturl, defining cur- dltlonal wflrl_ Is being cJ.=lldu(L_d t(_ deftri_ th=, to=

rent state-of-tht:-art transilllSslun technology, bricant chemli, tr]f, a,Jdltiv(, packaNi:, 4fl,J rll,_._HJCji

5uPl_ortpo ily tr,,l_ under car#fully controlled con- ca) and physl(al pr()p_rtlus In ord_:r t{ l(.trr(ll;i,dltlons, are rift.el ly nonexistent. If changes are which of th.m affect thu results shown.to he mad. lrJ gear and bearing techn(=l()cjy as ap-plied to transmlr.slon system,s, the effect of th_s !ran_mls,_ion Concept_technology must be assessed. Hence, the op(_ratingpararnetersof current staLe-of-the-arttransmis- Eased or=fundamental research perfr)rmedInslons must be evaluated. This would allow improve- mechanical components, an advanced 5O0-hp tranSmit,-meritS in compunents and new transmission concepts stun w_s designed and fabricated (Fig. lg). li.,t() he quantified with respect to noise, vibration, concept is a high-contact..rallo four plan.t-qeareff=clency, stresses, and thermal gradients, transmission for improved 1Odd capacity and llfe.

The high-contact-ratio gears are experte;d to res.lt

Four stat--nf-tt, e-art transmissions are being in lower noise and reduced dw_aml_ Ida,;.. The main

evaluated: (a) the 317-hp 0fl-58three planet gear bevel gear has been straddle-mountedto improvetransmlsslon, b) th. 317-hp 0H-58 four planet'qear deflection of the gear mounting, thereby improvingtransmission, (C) tn.)3CudO-hpSikorsky UH-b()A load sharing in the gear mesh. Ibis, too, is ex-transmissio., and (d) the 3000-hp roping UtIAS peeled tu result in lower noise and improved lit_.transmission. ]n ad,*lition,three advanced geared The planetary rzng gear has been cantilever-_nuuntedtransmissionconcepts are being investigatedunder to relieve problems inherent in the rlng-gear-to-this proqram: (a) advanced components transmission case,splint Interface. Rolling-element bearlnqs /:(Flq. 19), (b) beari,lglessplanetarx transmission wilt be manu3act_red from yacuum=tnduct!on-melted,(Fig. 20), and (c) split-torque transmission (F19. vacuum-arc-remetted (VIM-VAR) AISI M-50 material.21). The VIM-VAR AISI M-SO will restJlt in 1ong_r hearing

life. The bevel gear set was manufactured from

These t_ansmlssions are being evaluated on the VIM-VAR AISI 9310. The lubrlcatluns)'_temIs theriASALewis Research Cancer's 500.bp (Fig. 22) and latest technology of positiw' radial-.let)ubrl(_-JU()()-hp (FIq, 23) transmission facll;tles. These lion to the sun gear and splln_ [4el. This _'_11facilities are unique in tna& they can test both reduce wear and Increase the load-carryingcapacltyconventinnal geared and hybrid (tracti(mlgear) of the gear set.transmissions. Initially, these facilities arebeing used to establash basellae Informationon Ibis advanced transmlss_nnwhich _-lqn_ |_a Ibtransmissions designed usinq current state-of-the- ha'_ a weight-to-power ratio Fit U.?9 I1_of transmls-art design technlques_ Advanced analytical tech- stun weight per horsepower, a',compared with thvnlques which incl_dethose previously discussed standard 120 lh 317-hp Wi-Sh transmlss_Jnof ().3}_,will be used to examlne the many parameters that Iblhp. Prellmlnary tests have been COrlucte_ witl_affect the service life. efficiency, noise genera- the transmission (in the 500_hp test st_d.lion, and reliability of th_se transmissions.Further, the esperimental results will be us£d The transmission design has been n))dif!ed tueither to veri_y or to modify existing theory and allnw for the replacement of the bali ¢_arlng,, w_thcomputer codes, tapered~r(_lter hearings. Tapered-rolle-"hearings

on the output and input transmission st:arts offrrSnm. of the result_ of the evaluation of the greater Ioa(t capacity and longer life I_an the ball

eft Ic lency and qperat ing chararter!st ICS of the bearings.3]/-hp, three planet, OH-SB tPan_mi_ston ape _hownIn Figs. ?4 and PS. Fig. 24 shows the baseband The self-aligningbearingless planetary trans-frequency spectrum of the Oli-SR transmlssl-n show- mission (fig. 20) cover& a variety of Olanet_ary=lng the spiPat bevel gear ametltude compared to the gear confsgurattons, which Share the ¢(.:nmo(+char-spur gear amplltudr, The nn;se is tra(eable to acteristic that the planet carrier, or spider, istuot=h ki.emat.)c_a| error.. |t is geneeat]y tFue &ha& ehmnated, as tee conventional plan[t-mhuhtedlarger ampl itudes of vibeat!on occur at tooth me_$h bear|ng_. The bearings are etl mfnet_ed _ i_a_lfrequenc=es ()f tile spiral bevel gears. This was balancing th,, gears, which are separated tfl thr£tptPrmined from measurements on several different axial direction. AII forces and react i)ns are

transmissions, traflsmttte_ throu_jh the 9ea_ meshes and containedby simple rolling-rings. Thr cnncept w_s f lrst

The effe(t nf lubricant type ¢)n transmisslnn demonstrated by C=_rtls Wright L()rp, unn,r 5p.n_()r

elf I( IPn(y was dPtPrmln-d f(=rII different hlhri_ ship of the U.S. Army Aviati(m ResPar(l and l),,vPl "IIcants In the OH 5H iransmlssl(m [41 I. In addition, opment Lr_mmand[431, The 50()-hp bearlnqless plan

,. _ , J

1983016587-TSA07

ORIGINAL PAGE IgOF POOR QUALITY

etary transmission for the NASAprogram iS being merely 60?0 rpm, and the high-ratio varlant iS dedesigned to be comparable with the OH-SB baseline signed for an input speed of appr._lmaLely 36,[)iJhtransmission. The transmission weight-to-power rpm, Because the transmission can accommoOateit..ratio is approximately 0.27 Iblnp. hiqher input speed, th_ 40-1h t b | red,,It,), q,'a,

bo_ on the engine can be ellm|,ated. Hi*riLe I theA meant tu decrease the wetght-to-p_er ratio power train weight-to-power ratio can t,e a' tow a_

of a transmissvon or to decreas_ the unit stress 0.20 Iblhp.._ of gear teeth is by luad sharing through multiple

power paths, li_ls concept is referred to as the Con(_l__tn__(iomment_split-torque transmission [4]. Feasibility studieswere conducted on two variants of this concept The helicopter, more than any othrr contem(Fig. 21). porary aerospace or industrial t,novat.u¢_,ha_

placed severe performance demand_ on p_wer tran'_-lhe first variant is in th(, 50U-hp range with mission components such as bearings ar:,t gear_.

a single-engine input (Fig. 21(a)); the second is Wel]-deslgned mechanical components, 9odd materi-in the 3000-hp range with a two-engine I,put (fig. eli, end lubrication s_steJ)_s which are Intugrat_g21(b)). Insteadof a planetary-gear arrangement, into helicopter drive train systems Of, make thethe input power is split into two or more power _ifference between a hett¢op_r*f rel_abte, e¢o-Po)h_ end recom_ined in a bull gear to the output nomic _peration and failure, NASAtransmissionpower (rotor) shaft, research is oriented either to advance the state-

of-the-art in mechanical p,wer transfer technology

Preliminary weight estimates of the split- or to add to the fundamental body of kqowledge be-torque concept indicate that the weight-to-power longing to bearingb, gears, lubrication, rolling-ratio is approximately 0.24 Iblhp. Ibis concept element fatigue, l_fe prediction, traction phenom-appears to offer weight advantages over conven- ena, and _nechanicalpower transfer. Transmissionstiona] planetary concepts without using htglt- studied for application to helicopters in additioncontact-ratio gearing. The effects of incorpora- to the more conventional grated trans_issiuns in-tang high-contact-ratio gearing into the split- clude hybrid (traction/gear), bearingless plane-torque concept is expected to further reduce tory, and split torque transmissions. ConsiOeranletransmission weight, amounts of work are required in these areas to es-

tablish the validity of analysis and computer coors

A remedy to the speed-ratio and planet number developed to predict the p,.rformance, efficiency,limltationsof simple, single-row planetary systems llfe, and reliability of these transmissions.was devised by A.L. Nasvytis [44]. His drive sys- Real-time data recording, control and analysi_ fortom used the sun and ring-roller of the simple transmission testing are available for this purposeplanetary traction drive, but replaced the single on the NASA 50O-hp and 3OO0-hp helicopter irons-row of equal diameter planet-rollers with two or mission test stands. Both test stands are capablemore rows of stepped, or dual diameter, planets, of testing conventional and traction type helicop-With this new multiroller arrangement, practical ter transmissions. Results of this research Sho.ldspeed ratios of 25D to 1 could bc _htAined in a provide the transmission designer with analyticalsingle stage with three planet r_ furthermore, tools to design for minimum weight ant noise withthe number of planets carrying tar lo_,d in parallel maximum life and efficiency. In addition, the ad-could be greatly increased for a given ratio. This vantages and limitations of new and novel driveresulted in a significant reduction in individual systems as well as the more conventior, al systemsroller contact loading with a corresponding im- will be Ozfined.provement in torque capacity and fatigue life.

Referenc_To further reduce the size and the weight of

the drive for helicopter transmission applications, 1. Zaretsky. E. V., "NASA Helicopter lransmissionNASAincorporated with the second row of rollers, System Technology Program," G. K. Fischer, ed.,pinion gears in contact with a ring gear (Fig. 26). Prec., AOvanced Power lransmissloe_ Technoluug.vThe ring gear is connected through a spider to the _,--]_A-L'lP_O_J_,p_'-_[_OUtput rotor shaft. The number of planet-rollerrows and the relative diameter ratios at each con- 2. NasvyttS, A. L. and White, G., "H_rid &elfe_tact are variables to be optimized according tO the Traction Drives," 8. K. Fischer, ed., Prec.,overall speed ratio and the uniformity of contact Advanced Power Transmission Techrmlogy Sympo-forces. The traction-gear combination is referred slum,--NASACP-2210,-TiJ,_Z_p-:_-6)-172.to as the h#rid transmission.

3. Folenta, D. J., "Design Study of Self-Aligning.

Preliminary tests were conducted with a 50O-hp Bearingless, Planetary Transmiss*_)n,"G. K.low ratio variant of the hybrid transmission (Fig, Fi$cher. ed2. Prec.. _dvanced Pow,_r Iransmi_=78). The transmission, which has a weight-to-power stun Technology 5_!npuSTSm_-'NASACP-Z21_,-__._,Pt_io of 0,27 and a speed reduction Fat|o of 1):1, pp. 1_t-1_ ......could retrofit the OH-SB flel_opter. The _econdvariant of the hybrid transmission is referred to 4. White, G., *Helicopter Transmtssh)n with Split-aS the 5OO-hp high-ratio variant. This transmiso Torque &ear Coofig_ration," G. K. Fischer e cO,.stun has a speed reduction of t0|:!, the low-rlt|o Prec., Advanced Puwer Tr#nsm%sign Technology 1hybrid is designed for a speed input of approxt- Symposi_ N_ cP-P_iu, i§BZ, p_-, 14]-15D. ._

6 q

1983016587-TSA08

OF PO0!__ (4UALFIY

Savant=, M., Parl(}on. L. A., al,q Loy, d. ,i., |B. LurJlel|, H. W. am) kN',.t,,vv,'lt, °'iJv, _qlo ll.,ih5. "_el ahll it y Murl_l f(_r Planetary Gear lratn_," t(=ad ahd htre_,.In U f¢,r lt|qh ( ¢lnt(t, ( _=l lu '_$"4'

ASM[ papt:r n(). 8?-lJtl-_ll, lg_/. Gear,.," ,kaurn=l (Jr M_,charllLat _'_1_ J0 V=,l. |hu,No. l, Jan, lg/f|, pp. 6'_ /h.

b. Savage, M., Knurr, I_. J., and Eoy, J. J., "Llfeana Reliability M_clels for Helicopter Trant- 19. Lornell, k. W., %.l,pli,ui(t- _nit ',lr,,_,, ',,,n,,_ml_lons," AFlSpaper no. RWP-]6, 1982. tlvlty of 5put hear' leeih," ,hmrh_l of M,,,i=.h

Ical _slgn, Vol. 104, N¢). _, Apr. 19_1, pp.7. Lundberq, G. and Palmqren, A., =DynamiteCap. 441-45go

t try ot flolIHi 9 lie.rings," AC,IA PulytechnicG,M_chantcal Lngmeerin9 Series, Vol. 1_ No, 3, St). Plk% J, A,, "]¢ltera_t Iv,. Muir Ipi,, '_liur (,(,at1941. M_sh Dynamic kl)adPruqr_m," NA;,ALP IEbLI4,

_. Ltlndber 9, G. and Pa}mgr_n, A,, "Dynamic Capa-city of ROIier Bearings," ACIA Polytechnic., 21. Hustl_n, R. L. and Lily, 4. ,)., "%urta(:¢, bin)mr,tryMechanical Engineering Series, Vol. 2, No, 4, of Circular Cut S,l_ra! t_wl Guar'_t" Ju_r=_a} Of1952. MeChanical Desig_, Vet, )oq, NO, 4: Oct. 1982,

pp. 743-748.g. C_y, J. J., Town._end, D. P,, and Zaretsky,

_. V., "Analysisof Dynamic Capacity of Low 22. fluston,_. L., L1n, Y., and Coy, J. J., "T_othContact Ratio Spur Gears Using Lundberg- Profile Analysis_ of L tr;ular Cul Sl_lPat i_evetPalmoren Teeory," NASA IN D-80_79, Aug. 1975. Gears," ASMEpaper n,,. F?-UEl_79, l}fl?.

10. Coy, J. J., Townsend, D. P., and Zaretsky, 23. Host,n, N. and toy, J..., "ld_.al _ral i_w_lE. V., "Dynamic Capacity and Surface Fatlgue Gears - A N_w Approach lu _urface G.(m_try=°'Life for Spur and Helical Gear_," Journal of Journal of Mecha_:tcat [}_.-_fgn, Vol. 103, _. 1.Lubrication Tecnno}og), , Vo), 98, No. 2, Apr. O_n. 198t, pp. t2_-|_3.1976, pp. 267-276.

24. Lztvin, F, L.. C(_y,J. i., and _ahm_h, P., "lwu11. Coy, J. J., Townsend, O. P., and Zaretsky, Mathematicalb_Jd_lSof '.,_tral i_eV_.Gears Ap=

E. V., "An Update on the Life Analysis of Spur plied to Lubrication and Fatigue i_fe," jSML,Gears," G. K. Fischer, ed., Prec., Advanced IFTUMM, ASM[ an_;JSPE Trans., Internatlo,=alPower Transmission lecnnology $_nposlum, NASA Simpo_lum on (,earlnqan.)Fhlw(.r-'rra,:_iGTCSTS_oCP-2210, |982, pp. 421-433. _o-TTT, _ep. 19_, p-kT_.-_-_BG._........

12. Savage, M., Coy, J. J-, and Townsend, D.P., 25. lownser,d,D. P. and Zar,.tSk_,E. k'.,"Enter,rice"Optimal Design of Standard Gear Sets," G.K. aflClFailure Characteristi(:_ of M(mtflen VASE()Fischer, ell.,Pruc., A_vance_ Power Irons,is- X-2, CBS 6UO, and A]_] 931U Spur E_,._rs,""Jaur-

sion TechnolooqXS._gs'TunT,NA_/_I;f'--_O,-'T_JI]_, nal of Mechanical Desigh, Vol. IU3, No. 2, Apr.p-p_--43"5-45g. - IgB1, pp. 505-515.

}3. Savaqe, M., Coy, J. J., and Towns_.nd,O.P., 26. Towns(,d, D. P. and ,_ar(.t_ky,E. V., "Iff,Lt _)f"Optimal Tooth Nun_bersfor Compact Standard Shot Pe_ning on Surface FatlDuP Llt. _)f(orb,at-Spur Gear Sets." Journal of Mechanical Des' ,,Vol. 104, No. 4, Oct. 1982, pp. 749 to 7581.on' Ized an(_tlaraPnedAISI q310 Spur G(ars, NASATP 2047, 1g_2.

14. Sa_ago, M., COy, J. J._ and Townsend, D.P., 27. Akin, L. 5. an,lT_wn_en_I,b. P., ")_t(_M_h"The Optimal Design of Involute Gear Teeth Lubrication of Spur Gears With Arb_tr6ry k)ff_,_t

: with Unequal Addenda, NASATM 82656, 1982. Oil Jet .- Part 1, Fur Jl,t Velocity .es5 T,a,_ =)rEqual to Gear Velocity," NASA TM 8304U, }98_{.

1_, Anderson, N. E. and Loewenthal, S. H., "Effectof Geometry and Operating Conditlon5 on Spur 28. Akin, L. 5. and Town%end, D. P., W)nto MeshGear System Power Loss," Journal of Mechani- Lubrication of Spur Gears With Arbitrary Offsetcol Design, Vol. 103, No. I, Jan. 1981, pp, Oil Jet - Part If, For ,letVelocity Equal to or151-159. Greater Than Gear Velocity," NASA _-M83041,

1982.16. Coy, J. J. and Choo_ C. H., "A Method of

SPlecting Grid Size tn Account for Hertz De- 29. Wang, K. L. and Chang, Ih S., "A ((inputer (od_formation in Finite Element Analysis of Spur for Performance of Spur Gears," &. K. fischer,Gears," Journal of Mechanical Design, Vol. 104, ed., Prec., Advanced Power Transm_!°,ionlath.

No. 4, Oct. 1982, pp. 759-766. n_)o.__S.zm_, NASA LP-_I{}, _i, pp.5U3-b] / •

17, Chan9, S. H., Huston, R. l., and Coy, J. J.,"A Finite Element Stress Analysts of Spur Gears 30. Mark, W. D., "The Tran'_+er[uncti(m _thl)d f()rIncluding Fillet Radlul and Rim lhickness Ef- (=earSystem [_ynamlc_Applied to C()nv,.ntionalfacts," ASME paper no. 8_-WAIDE=15, Igi_?. and Minimum ix{ itat_(_nhearing Pe_ 9ns," NA_SA

a_ 36_6, 1987;

, 1983016587-TSA09

(_HIGII_AL Pi_G_ IS

OF POOR QUALITY

1]. I_r_e, ]. [.. et al., "Design of i Robotic Roller Bearings," G. K. Fischer, e¢_., Pruc.,kcoust_[ ]nten_ltj Heasurement System," Pre_- Advanced Power Transmission Techno|_y 5ympu-entatlon, ]U4th Ntg. Acoustical Society of _Tu_--,-'_"_]_'_-_,-T_,=pp.-20_ -='--America, Orlando, FA, 1962.

39. Co,, H. H. and _chui|er, F. T., "CaLcuLated and32. Latrine F. L., Goldrtch, R. N., Coy, J. J,, and Experimental Data for a ]]B-mrn Hun, Roller

2aret_ky, E. V., "Kinematic Precision of Gear Bearing to 3 Mi]lton bN0" Journal nf Luhrtcalrains," ASMEpaper no, B2-WAIDE-34, 1982, Lion lechnolo_y, Ve|. l(_, No. 2, Apr. 1981,

p_. _74-2B3.33. Lttvin, F. L., Ge|drtch, R. N., Coy, J. J., and

It

2aret_ky, E, V., _Prect_ion of Spiral _evel 40. Kleckner, R. J, and Dybe, G._ H_qh _pee_lGears," ASH[ p_per no. B?-HAiU[.33_ 1982. Sphertca| Rotter _r_n9 Analysts .nd Com_er_-

SO__tth Experimental P_rfurn_ance," G. K.34. Horrlson, F, R,, Ga_se|__o S., and Bovenkerk, Fischer, ed., Prec., Advanced Po_er Tran_ni_-

R. L., "_velopment of _mall Bore, High Speed sl_.on_j_m_.osiu____.mm,NASAL'P--_T_O-,-Tt]_._, pp. ----_apered Roller Be,ring," NASACR 165375, 1981. _39-25_.

35. Pa_kee, R. _., "Large-Bore Tapered-Roller 41. H_tchet), A. M. and Co)y, J. J., "L,bricant Ef_Bearing Performance and Endurance to 2.4 Hi1- fects on Efficiency of a Helicopter Transmis-|ion DN," G, K, F_cher_ cO., Proc., Advanced zion," NASATH 82857, 1_8_,Power Transmission Te_hnolog___CP:22[_, 1982,pp. 25_-Z_._ 42. Akin, L. $., Hross, J, d., and To_,;send,

D. P., "Study of Lubricant Jet Flow Pnefiomvn_

36. Parker, R. J., Pine1, S. 1., and Signer, H.R., in Spur Gears," Journal of Lubrication Tech-"Lubrication of Optimized-Oesign Taper,a-Roller nology, Vol. g7, No. 2, Apr. lg75, pp, 2_J-2_8,Bearings to 2.4 Million DN," NASATP 1714, 295.1980.

43. DeBruyne, N. A., "Design and bevei,_pmen_ Test-37. Parker, H. J. and Signer, H. R., "Lubrication tn_ of Free Planet Transmission Co,_cept,

of H_gh-Speed, Large-Bore Tapered-Roller Bear- USA_RDL-TR-74-27, 1974.ings , Journa_ of Lubrication Technology, Vol.100, No. I, Jan. 1978, pp. 39-46. 44. Nasvytis, A. L., "eultiroller Plan,)tary fr_c-

tion Drives," SAE paper no. 660763, Oct. 19b6.

38. Coe, H. H., "Predicted and Experimental Per-formance of Large-Bore High-Speed Ball and

B

1983016587-TSA10

r-_r)tr- .....• o ,

STEPPED PLANE1

PLANET BEARING _ Q

' _ m_PLANEIAR_ _UN /SYSTEM GEAR

_'3 1 // / PLANET BEARING

LIFE {MtLLION_ OF SUkROTATIONS}

RINGFIGURE 2. _EIBULL DISIRIBUTIONS FOR

SUN GEAR, PLANET BEARING, ANDFIGURE ], -C_POUND PLANETARY TRANSMISSION FOR A PLANETARYWITH

6EAR TRAIN. BALANCEDCOMPONENTS.

FIGURE _. -EXTERNAL 6EAR FIGURE 4. -INTERNAL GEAR• MESH, MESH,

1983016587-TSA11

oRiGiNAL p_G_ 13OF pOOR QUA;.T_'I'

I C"CONS]AN]_PI1] INGI-- scO.,NGj _ ,_

-N

:,/#', _'A " 14 TOOTH PINION

• _ _ "'_ --Z

9 _6.........io..... ;o

DIANETRAL PITCH 28 TOOTH GEAR t

FiGURE5. -DESIGNSPACEFORMINIMUMCENTERDISTANCESPACIN6 IN SPUR GEARS, FIGURE 6, -UNEOUAL ADDENDA MESH GEONETRY,

PITCH LM_ CPINION PITCH DIA, CM VEL,

100.0- 1.6_ 3.2 7 6.3-... ...-20.3,-5.1rl.3, " f

DIAt_]6 -8

z_ PITCH _o

99,0

_ _w

96,o2FIGURE 7. -EFFECT OF PtNtOP DIAMETER,

DtAHETR_J,. PITCH, AND PITCH LINEVELOCITY ON GEARSET EFFICIENCY AT A

K=FACTOR _F 31[X)i RATIO, 1.0$ PRESSUREANGLE,-20 ; PINION WIDTH/DEPTH RATIO,0,5; LUBR!CAN_ VISCOSITY, _0 CP.

10 41

1983016587-TSA12

.:i ur_o LEGEND""l __ .__,,L-STANDARD- 5M SIZE

i ' -- -- _ K-HIGH CR- 5M 511[i II ..... o M-HIGH CR- LG 511[i I

s_-4

.! _ _,._ .... _-.,_--":_ i

. :i 0 l d-

uaO

.... 26oo- -3_o--_obo ......5oo0: --_ INPUT TORQUE,, IN-LBF

:-i FIGURE8, -POWERLOSS PREDICTION OFNORMAL& HIGH CONTACTRATIO SPUR GEARS,

!:R

-a

M-I>". ; I,,_S,,J

:: _ CONTACT/ %./.CONTACT .am--: ¢/3

ELL IPSE_,/_PATH _'"I'-'¢¢1,_

- / r ./ ,.,.-'_°_=// m--

9310 600 x-_' 5.P,

FIGURE 10. -FATIGUE LIFE FO_ FOURFIGURE O, -TOOTH CONTACTPATH GEARMATERIALS CONPAREDTO BASE-

DESCRIPTION. LINE AISI 9310 NATERIAL,

1983016587-TSA13

ORIGINAL P,",_E rc

OF POOR QUALITY

I)

!

OFPoo_r_u_,uTy

,_._NOISE FIELD

._' INSTRUMENTATION

ACOUSTICINTENSITY \\

-PROBE ____._I"i)IGITAL]

SPECTRUM L_J

ANALYZ,_ CALCULATOR

FIGURE 14. -SCHEMATIC OF RAII_ SYSTEM.

IDEAL ZaSTEADY KINEMATIC._MOTION ERROR

: _ ..... .f__ _"_ACTUALI ,'_TH R _ MOTIONMESH

CHANGEPOINT !

6EAR ROTATION ANGLE

FIGURE 15, -KINEMATIC ERRORFUNCTION FOR THE FIGURE 16. -TOOTH SURFACESWITHMESH OF SEVERAL REAR TEETH, CLEARANCEINDUCEDBY E;'RORS.

13!

1983016587-TSB01

OF POOR QUALIFY

FIGURE17. -TAPERED-ROLLER BEARINGS REPLACEBALL ANDCYLINDRICAL ROLLERBEARINGS ON INPUT PINION FORHELICOPTER TRNSMISSION.

BASELINE DESIGN :I

lalO

SIGN

BEARINGHEAT

6ENERATI ONoBTU/M IN

I . I li I0 -- _ I0000 I$OGO 20_0

SHAFT SPEED, RPM

FI6URE 18. -IMPROVED PERFORMANCEOF ADVANCEDHIGH-'SPEED TAPEREDROLLER BEARINGS.

1,q

_4

q.-

] 983016587-TSB02

ORIGINAL P.... _. _OF POOR QUALITY

• 14IPM

II

• --1

!

FIGURE19. -500 HP ADVANCEDCOt4PONENTSTRANSMISSION.

FIGURE 20. -SELF ALIGNING BEARINGLES5PLANETARY(LONRATtO VERgtON),

t5!

.o

t

1983016587-TSB03

OF POOR QU&LIT_,

(A) SINGLE INPUT. (B) DUAL INPUT,

FI 6URE 21, -CONCEPTUALSKETCHSPLIT-TORQUE TRANSMISS ION.

,q16

Ii

1983016587-TSB04

6 i ............ ,......

SPIRAL BEVEL

ACCELERATION,G PEAK-PEAK

ORtC!;,'/,"W.C',:.r.c_OF POORQUALITY

+.I

f I(_bl_l ;++',. -=J(X) lIP HYhRIIJ Hit I((JPII:H

| l_/,P+',t,+ I !,!_ I(IN,

1983016587-TSB06