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Contents
2 Projectplanning 11-26 2.1 Listofformulae 12 2.2 Suggestionsforinstallation 13-142.2.1 Verticalinstallation 132.2.2 Horizontalinstallation 14 2.3 ServicelifeLh 15 2.4 Guidelinesforuse 15-162.4.1 Dirtprotection 152.4.2 Corrosionprotection 152.4.3 Itemsrequiringregularlubrication 16 2.5 Ambienttemperatures 16 2.6 Precisionratings 172.6.1 Axialplay"a" 172.6.2 Lateralplay"b" 172.6.3 Toothprofileplay 172.6.4 Screwleaderror 17 2.7 Specialoperatingareas 18 2.8 Dimensioningofwormgearscrewjacks 19-212.8.1 Flowdiagram 192.8.2 Example 202.8.3 Manualoperationforliftingelements 202.8.4 Motordriveforliftingelements 202.8.5 Adjustmentandstoppingaccuracy 21 2.9 Permittedoperatingsettings 21-222.9.1 General 212.9.2 Operatingfactors 22 2.10 Dimensioningofliftingsystems 232.10.1 Flowdiagram 232.10.2 Example 23 2.11 Schematicdrivesystemlayout 24-262.11.1 Singledriveunit 242.11.2 Multi-screwliftingsystem 252.11.2.1 Mechanicallysynchronized 25-262.11.2.2 Electricallysynchronized 26
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2.1Listofformulae
Index
HE Wormgearscrewjack
Anl Liftingsystem
Ku Ballscrew
Tr Trapezoidalscrew
zul Permissible
ConfigurationconformingtoEN1570,EN280,EN-1756,EN1493(VBG14)Leadangle:2,4°<w<4,5° Ó Motorwithsinglebrakingtorquew>4,5° Ó Twoindependentbrakingsystems
StandardsfortheatrestagesandbroadcastingstudiosBGVC1(VBG70)Similar to configuration conforming to VBG 14, althoughself-locking screw is not an absolute requirement if alltorquetransmittingcomponentsaredesignedtowithstandtwicetheratedload.
Abbr. Designation Measuringunit Formula
w(•) Leadangle ° w=arctan[Ph/(d2*p)]
Self-lockingduringshutdown*:2,4°<w<4,5°
(Self-lockingoutofactuation:w<2,4°)
Notself-locking:w>4,5°
hAnl Liftingsystemefficiencyrating
hHE Wormgearscrewjackefficiencyrating
a Acceleration m/s2 a=v/(60*t)
As Numberofloadcycles
C Dynamicloadrating kN
Co Staticloadrating kN
d2 Pitchdiameter mm
ED Dutyratio %/hr ED=[lift*As/(60*v)]*100%
Fdyn Dynamicaxialforce(=liftingforce) kN
Fstat Staticaxialforce(=retentionforce) kN
HU Liftperrotation mm HU=Ph/i
i Transmissionratio
Lh Servicelife h Lh=(C/Fdyn)3*106/(n2*60)
n1 Inputspeed min-1
n2 Outputspeed min-2 n2=n1/i
P Powerrating kW P=Fdyn*v/(60*h)
Ph Screwlead mm
pv-value Surfacepressurexslidingspeed N/mm2*m/min
pzul Permittedsurfacepressure N/mm2
t Time s
T1 Drivetorque Nm T1=P*9550/n1
T2 Outputtorque(=screwtorque) Nm
TA Startingtorque Nm TA~T1* 1,3
v Liftingspeed m/min v=n1* Ph/i
(•)Vibrationsandoptimizedslidingpropertiesmayaffecttheself-lockingsystem.Ifindoubt,useamotorbrake.
ProjectplanningProjectplanning
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2.2Suggestionsforinstallation
2.2.1Verticalinstallation
Recommendedarrangementforlargeliftingcapacitiesandlongscrews
Tensileload
Design:Configurationtype1Withclimbingscrewjacks(withoutprotectiontube)
Compression-loadedscrewswithoutlateralguides
DimensioningofscrewaccordingtoEuler’scaseI
Design:Configurationtype1Withliftingscrewandprotectiontube
Arrangementwithcompression-loadedscrew,possiblewithorwithoutadditionalguides
DimensioningofscrewaccordingtoEuler’scaseIIIandcriticalscrewspeed
Design:Configurationtype2Withrotatingscrewandtravellingnut
Swivellingmovementsrequirearticulatedmounting
DimensioningofscrewaccordingtoEuler’scaseII
Design:Configurationtype1Withliftingscrew,twoguideringsandprotectiontube
S=safetyclearanceSeechapter7"Accessories”fordetailsofallrequiredadd-onitems(connectingflanges,swivelmountingbasesetc.).
Pict.4
Pict.1
Liftingplatform(Load)
Connectingshaft
usea
ble
stro
ke
HeadtypeII
HeadtypeIV
Pict.2
Connectingshaft
usea
ble
stro
ke
Liftingplatform(Load)
Pict.3
usea
ble
stro
ke
Connectingshaft
Standardtravellingnut
Travellingnutwithsphericalpivotingsuspension
Liftingplatform(Load)
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2.2Suggestionsforinstallation2.2.2Horizontalinstallation
Intermediatebearing-supportofa12mscrew
Standard once-piece screws can be made in lengthsofupto6m(3mforscrewsmadeofrust-freemate-rial). Longer screws are supplied in sections to makeinstallationonsiteeasier.
Specialtravellingnut
If critical screw speed is exceeded (only applies toconfigurationtype2=rotatingscrew),thescrewsmustbeadequatelysupported.Thisrequirestheuseofourspecially-supplied intermediate bearings and travellingnuts(seephotos).
Arrangementwithcompression-andtension-force-loadedscrewWithguidessuppliedonsite
DimensioningofscrewaccordingtoEuler’scaseII,ifscrewretainingforceisinsuffici-ent.Otherwise,applyEuler’scaseIII
Design:Configurationtype1Withclampedscrewandlineartraversingdriveaxis.
Arrangementwithcompression-andtension-force-loadedscrewWithguidessuppliedonsite
DimensioningofscrewaccordingtoEuler’scaseIIIandcriticalscrewspeed
Withscrewspre-adjustedtotensileloadÓ
Dimensioningaccordingtocriticalspeedonly
Design:Configurationtype2Withrotatingscrewandtravellingnut
Pict.5 Pict.6
Pict.7 Pict.8
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2.3ServicelifeLh
The design and construction of Pfaff-silberblau worm gear screw and quick-lifting jacks are based on our long years ofexperienceinthefieldandtheyhavealongservicelifeiftheinstructionsintheoperatingmanualsareobserved.
Themaximumloadvaluesgiveninthecataloguedata(tablesofsettings)arebasedonaservicelifeofminimum500operatinghours.
2.4Guidelinesforuse
2.4.2Corrosionprotection
Corrosionprotectedaluminiumhousingsfittedtothefollowingranges:SHE Size0.5and1.1MERKUR SizeM0,M1andM2HSE Size32and36.1SHG SizeG25
Surfacecoatingforallothersizes:•SHEandHSEhousingswithseries-applied primecoat•MERKURandSHGwithphosphatecoatedhousings
Optionalcorrosionprotectionforspecialconfigurations:Availableforallranges:•Specialcoatings•Screwsandscrewheadsmade ofmaterial1.4305,1.4301,1.4571•Worm-driveshaftsmadeofrust-freematerial•SHErangeincompletelyrust-free materialconfiguration
Corrosionprotectionprovidedbysurfacecoatings:Availableforallranges:•Tenifertreated(salt-bathnitrided)•Hard-chromeplateddriveshafts
SHGG25(aluminiumhousing)
Screw Gearinglayout Bearinglayout
TrandSscrew Kuballscrew NorL Thrustandradialbearings
•Thesevaluesareforguidanceonly,
asexactcalculationisnotpossible
•Decisivelayoutfactorsaresurface
pressureandslidingspeed
(pv-value,pzul)
• Guaranteedrelubrication
• Idealinstallation
•Calculation:
Lh=(C/Fdyn)3*106/(n2*60)
Worm-drivegearing:
• SHEstandardwormscrewjackand
MERKUR:approximatevaluesaccording
toDIN3996-D
• InthecaseofHSEhighperformanceworm
gearscrewjack,accordingtoDIN3996-C
Bevelgeartoothsystem:
•SHGquick-liftingscrewjacks,Lh=fatigueendurable
• Calculationsaccordingto
DINordatasuppliedby
thebearingsupplier
2.4.1Dirtprotection
• Leakproofingofallrangesbymeans ofrotarylipsealsfittedtodriveshaftsisstandard• EnclosedhousingconfigurationonHSEundSHG rangesusingadditionalseals• Screwprotectiontubefortype1
Optionalliftingscrewprotectivecovers:• Flexibleprotectionbootsmadeofvariousmaterials toprevententryofdirtandforoutdooruse (water-proof)• Spiralspringcoverforuseinextreme environment(flyingswarf,weldingsparks)
Specialconfigurations:Specialconfigurations,e.g.foruseunderwaterorathightemperatures,areavailableonrequest
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2.4Guidelinesforuse
Ifaccesstothescrewitselforthelubricationpointsonthehousingisdifficult,werecommendtheuseofacentrallubricationsystemorautomatic lubricantdispenser (seechapter7.8).Ourcomponentscanbesuppliedwith thenecessaryscrew-inconnections for thispurpose.
SHEandMErKurrange
Configuration Lubricationpoint
Type1 guidering,protectiontube,housing
(gearinglayout)
Type2 travellingnut,housing(gearinglayout)
HSEandSHGrange
Configuration Lubricationpoint
Type1 guidering,protectiontube
Type2 travellingnut
2.5Ambienttemperatures
2.4.3Itemsrequiringregularlubrication
Standard
-10°C + 40°C
T< -10°C
-Speciallubricants,max.-30°C
-Specialmaterials(onrequest)
+ 40°C<T<_80°C
-Speciallubricants,max.+80 °C
-SpecialmeasuresT>80°C
(onrequest)
Note:PleasetakeourreducedperformanceorED-(dutyratio)
valuesintoconsiderationiftemperaturesdeviatefromthestandardsgiven.
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2.6Precisionratings2.6.1Axialplay„a”
Axialplayhasnoinfluenceonpositioningaccuracyinthecaseofone-sideload,astheflanksofthescrewthreadprovidesupport.
2.6.2Lateralplay„b”StandardLateralplay„b”occursonlyinthecaseoftype1,asaresultofplaybetweentheguideringandtheouterdiameterofthescrew.Itcomesuptoabout0,2mmandeffectsa linearcalculativedeviation„b“dependingonstroke length.Theamountofplay„b”canbereducedbymeansofasecondguidering.
Specialconfiguration2ndguideringwithreducedplayandadditionallygroundscrewmaterial.
2.6.3Toothprofileplay
Wormgeartoothconfiguration
Bevelgeartoothconfiguration
The tooth profile play (when new) of 0,1 – 0,3 mm varies,depending on the size of the unit resp. centre distance ofshafttowheel,withtherateofwear.
Toothprofileplayof0,05–0,1mmkeptconstantthroughoutservicelifeofunit.
2.6.4Screwleaderror
TrapezoidalscrewthreadconformingtoDIN103T1; ButtressscrewthreadconformingtoDIN513
Whirledscrew(standard)±0,05mm
Rolledscrew±0,1mm
Trapezoidalorbuttress-threadscrew
Standard
0,1mm[a[0,3mm,dependingonsize
Modifiedconfiguration:
Axialplaycanbereadjusted
Ballscrew
Singleflangenuta[0,05mm
Initialtensiondependingonsizeofball
0,01mm[a[0,03mm
Pre-stresseddoublenuta[ 0,01mm
BallscrewthreadconformingtoDIN69051T3
Whirledscrew(standard)ToleranceclassificationT7;P300=0,052mm
Groundscrew;toleranceclassificationT1-5;P300=0,006-0,023mm
Rolledscrew;toleranceclassificationT9;P300=0,1mm
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2.7Specialoperatingareasofapplication
• Specialsealingwith non-toxiclubricants
• Corrosionprotection (rust-freematerials)
• Travellingnutsmadeof self-lubricatingmaterial
e. g. use of approved materi-als with inspection certificatepursuanttoDINEN102042.2-3.1B-3.1C
•Greasingwithradiationresistantlubricants
•Earthquakeproofconfiguration
Wehavemanyyearsofexperienceintheareaofspecialapplicationsfor
linearactuatortechnology,andcanofferthefollowingservices:
Underwater Inpotentiallyexplosiveareas
Wormgearscrewjacksandliftingsystemsinspecialconfiguration
Incontaminatedareas
•Projectplanning
•Designsupport
•Materialtestingandcertification
•Supervisionofinstallation
proceduresandinitialstart-up
•Project-relateddocumentation
• Wormgearscrewjacks accordingto ECDirective94/9/ECATEX inequipmentgroupII- Zone1/21(2/22)withc/k/b protectionandtemperature classT1andT4
• Useofapprovedelectrical components,suchasmotors, limitswitches,pressure-resistant sealedbrakeunitsconforming tothecorrespondingtypeof protectionandtemperature class
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2.8Dimensioningofwormgearscrewjacks2.8.1Flowdiagram
Selectedgearsizecanbeapplied
Tensileload
No
Screwdiameterasdisplayedinchapter3.4.2Note:Areinforcedscrewdiametercanbe
usedfortype2jacks(rotatingscrews)
Compressionload
Checkaccordingtochapter
2Projectplanning3.1Constructionsupport
orconsultourscrewjackspecialists
Hotline:Phone+49/8233/2121-4100
TechnicalinformationSeechapter3
Forexample:Efficiencyratingsandperformancetables
Yes
Areadditionalconditionstobeobserved?
•Extraordinaryoperatingconditions•Shocks/Strokes
•Lateralloads•Dutyratio>20%/h
•Standardstobeobserved,e.g.VBG14(elevatingplatforms),
BGVC1(theatrestagesandbroadcastingstudios)
Pre-selectiondependsonperformancelimitsofscrewjackanddiameterofscrew.Tablesofsettings,chapter3.4.1
DeterminedutyratioED[%/h];determinepowerratingP[kW](seeformulaecollectioninchapter2.1)
Dimensioningofscrewaccordingtoloaddirection
Axialforce[kN]Fdyndynamicforce
Fstatstaticforce(retentionforce)Liftingspeedv[m/min]
Stroke[mm]Determineconfiguration
(type1ortype2)
Euler’scaseI
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2.8Dimensioningofwormgearscrewjacks2.8.2Example
2.8.3Manualoperationforliftingelements
2.8.4Motordriveforliftingelements
Motordesigns:
requiredstartingtorque TA~1,3xTN
Highliftingspeeds,e.g.servodrivesystem Inertialmassandaccelerationtimeare
decisivefactorsforconfiguration
Screw Frombucklingdiagram Tr50x9
Pre-selectionofwormgearscrewjack Chapter3.4.1 HSE63.1
Requireddriveperformance 2,0kW Performancelimitaccording
totableofsettings,chapt.3.4.1Perf<pzul=2,3kW
Dutyratio 11%/h Forformula,seechapt.2.1 EDvorh<EDzul=20%/h
Selectedmotor 2,2kW,1500min-1
SelectedsizeHSE63.1isok
RatioN
T1=higher
Lift/Rotation=larger
Manualoperation
RatioL
T1=lower
Lift/Rotation=less
TakepossibledrivetorqueT1and/or
manualforceintoaccount
(valuesbasedonpastexperience:
approx.150tomax.200N)
NoED(dutyratio)checkrequired
Takethetypeofmotor(three-phase,DC,
hydraulicetc.)intoaccountwithrespecttostart-upchar-acteristics,impactcoefficient
andsoon
Observetheadditionalfrictioncoefficientsof
theguideelementsetc.
Observethemax.permitteddrivecapacityoftheliftingelement.
Seechapter3.4.1
Observethemax.per-mitteddutyratio.Seechapter3.4.1
Motordrive
Guidesfittedonsite YesÓ
Euler’scaseIII
Loadcycles/hour 10
Travelperloadcycle 1200mm
Configurationtype1(liftingscrew)
Singledriveunitwithmotor
RequiredaxialforceFdyn 20kN
Requiredliftingspeedv 1,9m/min
Requiredlift 1200mm
Selectedconfiguration Seechapter3.2
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2.8Dimensioningofwormgearscrewjacks2.8.5Adjustmentandstoppingaccuracy
The levelof adjustmentaccuracydependsmainlyon theprecisionof thescrew (seechapter2.6).Positioningaccuracy isinfluenced,inthecaseofmotor-actuatedunits,bytheelectricalcontrolandregulatingsystem,thecontrolsystemofthebrake,andbytheadjustmentprecisionofthelimitswitches.
IMPOrTANT:DONOTallowmotor-actuatedcomponentstocollidewithfixedend-limitstops!
2.9.1General
Lateralforceonscrew
Fs
Fordetailsofpermittedvalues,
seediagramsinchapter3.4.8
Drivecapacity
PHE<pzul
PHE=Fdyn*v/(60*hHE)
Forcalculationdetails,
seechapter2.1
Standardlayoutat
20%ED/hourand20°C,or
10%ED/hourand20°C
Dynamicandstatic
compression/tensileload
Fdyn/Fstat
Configurationaccordingtotableof
settingschapter3.4.1and/orbuckling
diagramsinchapter3.4.2
Axialloadondriveshaft
Fa
Noaxialloadspermitted
(Thisshouldalsobetakeninto
accountwhenfittingcouplingsand
connectingshafts)
radialloadondriveshaft
Fr
Fordetailsofpermittedvalues,see
chapter3.4.9
Drivetorque
T1<Tzul
T1=PHE*9550/n1
Forcalculationdetails,seechapter2.1
F a
Fs T1
Fr
Fdyn/Fstat
2.9Permittedoperatingsettings
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Powerfactorsk1,k2andk3applyspecificallytoHSEhighperformancewormgearscrewjacks.Theymustnotbeappliedtostandardwormgearscrewjacks,Merkursystemsorquick-liftingscrewjacks.
2.9Permittedoperatingsettings
Powerfactork1
Powerfactork1isthelostenergy(quantityofheat)thatcan be dissipated at ED 20 %/h and 20 °C ambienttemperatureofHSEwithoutanoutsidecoolingsystem.Thesteady-statetemperatureinthiscaseis80°C.
pzul=k1*k2*k3/(1-hHE)
Dutyfactork2
The duty factor k2 is the correction value used to in-crease or decrease the permitted drive capacity pzulwithadeviationof20%ED/h.At20%ED/hor30%ED/10minisk2=1.Ifthedutyratiodeviatesfromtheestablishedsettings,k2canbedeterminedusingthediagramshownhere.
Temperaturefactork3
Atnormaltemperaturesof20°C,thisfactoris1.Intheeventoffluctuatingambienttemperatures(=q),thisfactoriscalculatedasfollows:
80–q k3= 60
HighperformancewormgearscrewjackHSE
2.9.2Operatingfactors
StandardwormgearscrewjacksSHEandMErKur ReductionofEDrelativetoambienttemperature
Ambienttemperature[°C] 50° 60° 70° 80°
inthecaseofscrewjacksSHEandMErKur
Maximumpermitteddutyratio
%/h 18 15 10 5
%/10min 36 30 20 10
CAUTION:MaximumoperatingtemperatureHE=80°C
Ope
ratin
gFa
ctor
k2
RelatedTime(min)
Projectplanning Projectplanning
SizeHSE 32 36.1 50.1 63.1 80.1
Powerfactork1[kW] 0,40 0,64 1,0 1,62 2,43
SizeHSE 100.1 125.1 200.1
Powerfactork1[kW] 3,30 5,41 13,30
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2.10Dimensioningofliftingsystems2.10.1Flowdiagram
2.10.2Example
Technicalspecifications:Fges=60kN(dyn.andstat.)v=1,9m/minED=20%/hSchematicview4.1Three-phasemotorBevelgearboxi=1:1
Overallforce[Fges]ofthesystem[kN]
Liftingspeed
Selectschematicdrive-systemlayout(chapter2.11)
Numberandarrangementofscrewjacks,typeof
motor,connectingshafts,bevelgearboxes,
couplings
Configurebevelgearboxes,couplings,
connectingshafts(accordingtotorque
andturningspeed)
hAnl~0,8
hHEasshowninchapter3.4.1or3.4.5
*Factorforunequal
loaddistribution=1,3
Observethemaximumdrive
torqueondriveshaftof
screwjack
Ifnon-self-locking
liftingsystemsareinoperation,
fitthemotorwithaspring-
actuatedsafetybrake.
TAnl=minimumnominaltorque
ofmotor
startingtorque
TA~TAnl*1,3
Fges*v PAnl= 60*hHE*hAnl
PAnl*9550 TAnl= n1
PAnl*1,3 PHE= Numberofscrewjacks
Checkscrewjackasshowincapter2.9
DeterminetypeofmotoraccordingtoPAnl,turningspeed,with/withoutbrake,
torqueTA
FHE=60kN/4*1.3Pre-selectionofscrewjackaccordingtochapter2.8
Ì HSE63.1,Tr50x9,
FHE=19,5kN hHE=0,311;PHE=2,0kW,hAnl~0,8
PAnl=7,63kW Ì motorselection7,5kW,n1=1500min-1 Ì motor132M/4
TAnl=49Nm Ì TKeg=25Nm,i=1:1(chapter4) Ì bevelgearboxK11.13
TGW1=25Nm,n1=1500min-1;observemax.lengthaccordingtonkrit(chapter6) ÌconnectingshaftZR28/38
TGW2=12,5Nm,n1=1500min-1;observemax.lengthaccordingtonkrit(chapter6) Ì connectingshaftZR24/28
Bevelgearbox
Motor
Screwjack
Connectingshaft2
Connectingshaft1
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2.11Schematicdrivesystemlayout
2.11.1Singledriveunit
Wormgearscrew jack–coupling–motor inconfigu-rationB3(base-mounted)
Wormgearscrewjack–coupling–IECflangeincon-figurationB14orB5(IECflange-mounting)
withcoupling withIECflangeandcoupling
Pfaff-silberblauwormgearscrewjacksandquick-liftingscrewjackscan be used as either single drive units (see chapter 2.11.1) ormulti-screwliftingsystems(seechapter2.11.2).Multi-screwliftingsystems with mechanical synchronization are driven by a singlemotor,whichmakes them impervious tounequal loaddistributionanditsnegativeeffectsonthesynchronizationofthescrewjacks.Multi-screw lifting systems with electrical synchronization aredistinguished by their low requirements in terms of mechanicalconnectingelements(andthereforelackofrunningnoise),buttheydorequiremoresophisticatedcontrols.Preciseconfigurationofthedrivemotors, inconjunctionwithamaster-slave layout,producesthecorrespondingexactsynchronizationofthedrivesystems.Onceyouhavedecidedonthebestlayoutforyourneeds,youcanestablishwhichbevelgearboxes,couplingsandconnectingshaftsaretobefitted.Thefittingofpillowblockscanmultiplythespeed-dependentlengthoftheconnectingshafts.
Note:If quick-lifting screw jacks are in use, correct configuration caneliminatetheneedforbevelgearboxes.
Schematicview1.1
Symboles
Screwjack
Connectingshaft
Coupling
Standardmotor
Spurgearmotor
Pillowblock
Bevelgearbox
IECflange
-Wormgearmotor-Bevelgearmotor
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2.11Schematicdrivesystemlayout2.11.2Multi-screwliftingsystem
2.11.2.1Mechanicallysynchronized
Schematicview3.1
Schematicview3.2
Schematicview3.3
Design"C”Onlypossiblewithratio1:1
Schematicview2.1
Schematicview2.3
Schematicview2.2
Schematicview2.4
Design"C”Onlypossiblewithratio1:1
Design"C"ordesign"D"Allratiospossible
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2.11.2.2Electricallysynchronized
Master
Slave3
Slave1
Slave2
2.11Schematicdrivesystemlayout
Schematicview4.1 Schematicview4.2
Schematicview4.5
Schematicview4.3
Idealtorquedistribution
Design„C” Design„D”
Anyratiopossible,but„C”and„D“mustbethesame
Design„A”
Design„F”
Design„C”
Design„E”
Anyratiopossible,but"A”and"E”mustbethesame
Pillowblocksonlyrequiredwhenexceedingthecriticalspeed
Onlypossiblewithratio1:1
Closeloopfrequencycontrol
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