A Member of the Schaeffler Group

Gearing up for tomorrow

English

Our attention is focused towards you,your projects and your future visionfor tomorrow’s automotive world. In fact, over 8,000 LuK Group employ-ees are there for you. Skilled and experienced project teams are at yourdisposal, ready to transform your requirements into reality – LuK tech-nology can be incorporated into your vehicles in a simple, straight-forward way.

The Black Forest town of Bühl ishome to the headquarters of the LuKGroup’s global automotive supply operations. One in every four new carsaround the world rolls off the as-sembly line fitted with a LuK clutch.LuK products aren’t just used in cars,but in commercial vehicles, busesand tractors.

With 16 worldwide production siteslocated in Germany, Brazil, GreatBritain, India, Mexico, South Africa,Hungary and the USA, we’re alwayscloser than you think.

Transmission technology has devel-oped into an innovative driving forcein the automotive industry. Your ex-pertise and our specialist knowledgeenable us to act as a trigger for numerous developments which makethe car safer, more comfortable andmore economical. Examples of thisare the LuK CVT components andLuK’s views on twin clutch gearboxes. It is transmission technology whichadds considerably to the car’s fascina-tion. It is the way in which the cardrives that generates enthusiasm anddriving pleasure. Enthusiastic driversare our common goal.

We are there for you!

LuK’s hydraulic applications are alsostrongly influenced by the factorssuch as comfort, safety, economy anddriving pleasure. Innovative pumpsare produced to provide power forsteering systems – especially on com-mercial vehicles, and for active sus-pension and stability control applica-tions. Tandem pumps ensure thenecessary injection pressure for fuel-efficient engines and ensure a safersupply of energy for the servo function.

So, how can we be of service to you inthe future?

Dr.-Ing. Peter Gutzmer

ChairmanLuK Group (Board)

2

Dual Mass Flywheel 4

Clutches 6

Release Systems, Products for Agriculture 8

XSG Family: Gearbox Automation 10

Continuously Variable Transmission 12

Torque Converter, Crankshaft Damper, Belt-Driven Starter Generator 14

Power Steering, Chassis and Transmission Pumps, CO2 Air Conditioning System 16

Vacuum and Tandem Pumps 18

Awards, Quality, the Environment, Recycling 20

Development Expertise 22

Contents

3

4

Engine Spee

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Conventional ClutchFlywheel with Clutch Clutch Disc with Torsion Damper

Gearbox

50

0

–50

Time

LuK Dual Mass Flywheel (DMFW)

Damped Vibrations for Undamped Driving Pleasure.

Modern engines can be driven at ex-tremely low rpms. The trend is towardever increasing engine torques. Wind tunnel-optimized bodies are creating less wind noise. New calcu-lation methods are helping reduce vehicle weights and weight-savingconcepts are boosting engine effi-ciency as well. The addition of a fifthor a sixth gear can also reduce fuelconsumption. Thinner oils are makingprecise shifting easier.

In short: The sources of noise are increasing and natural damping is decreasing.

What has remained is the principle of the piston-stroke engine whosecyclical combustion processes excitetorsional vibrations in the drive train –the unpleasant consequences of

which are gear rattles and bodybooms. Drivers who are accustomedto increased comfort no longer accept such background noises.

The job of the clutch is now moreimportant than ever – in additionto engaging and disengaging, it must effectively isolate the engine’s vibrations.

Physically, this is easy to solve: Themass moment of inertia of the trans-mission must be increased withoutincreasing the mass to be shifted.This dampens the engine’s torsionalvibrations and brings about the desired comfort level. The process reduces load on the transmission at the same time.

It’s All in the NameLuK was the first manufacturer in Europe to develop and sell a dualmass flywheel in large-scale standardproduction that was able to realizethis physical principle.

The name says it all: The mass of theconventional flywheel was simply splitin two. One part continues to belongto the engine’s mass moment of iner-tia, while the other part now increases

Dual Mass FlywheelPrimary Flywheel

Torsion Damper

Secundary Flywheel with Clutch

Rigid Clutch Disc

Engine Gearbox

Spee

d Fl

uctu

atio

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/min

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50

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–50

Time

Torsional Fluctuation Measurement in Drive

Engine

Gearbox

5

Sounds Good – Feels Good

These include using multi-stage char-acteristic curves or friction-optimizedlubricants. A clutch disc with a tuneddamper helps particularly with rear-wheel drive vehicles.

The LuK DMFW thus provides agreater degree of comfort in everydaydriving operation.

LuK DMFW – The Advantages:

First-class driving comfort

Absorbs vibrations

Prevents noise

Allows comfortable low-rpm driving

Saves fuel

Relieves the crankshaft and transmission

the mass moment of inertia of thetransmission.

The two decoupled masses arelinked by a spring/damping system.One clutch disc, without a torsiondamper, between the secondarymass and the transmission handlesthe engaging and disengaging func-tions. A favorable side effect is thatthe transmission is easier to shift because of the low mass to be syn-chronized, and there is less synchro-nization wear.

The use of a very flexible spring between the decoupled masses in-creases the decoupling level of thetransmission even further. The reso-nance of the system, which must run continuously when starting andshutting off the engine, can also beimproved.

The optimal use of space of the lubri-cated arc spring damper used by LuK allows for an especially flexiblespring. In addition, it generates adamping characteristic that depends

on the effective torque: If there areincreased vibrations in the reso-nance area, the arc spring damperautomatically reacts with increaseddamping.

But with small vibrations, such asthose that are typical of normal driv-ing operation, only slight damping is generated even at high torques.That is ideal, because in that range,high damping would only deterioratethe decoupling.

Various measures can be used to further optimize the arc springdamper for better decoupling depend-ing on the vehicle’s requirements.

The constant trendtowards higher en-

gine torque as comfortdemands increase simul-

taneously calls for clutches that onthe one hand can transmit very highforces/torques and on the other handhave the lowest possible operatingload. The power belongs on the road,not at the pedal.

Diaphragm Spring ClutchesThe invention of the diaphragm springclutch and its first large series produc-tion by LuK was a major developmentstep. The diaphragm spring in theclutch pressure plate generates therequired clamp load on the frictionfacings. Together with the diaphragmspring finger, it also functions as thelever to operate the clutch.

Self-Adjusting Clutches (SAC)Since clutches are subject to wearduring use in the vehicle, LuK, as thefirst clutch manufacturer, put a greatdeal of effort into developing a type of wear compensation system for theclutch, and put it in production in1995. The self-adjusting clutch (SAC)uses a load sensor (sensor-diaphragmspring) to activate its wear compensa-tion by turning a ramp ring. This com-pensation mechanism has made itpossible to decrease operating loads.

The compensation for the clutch wearhas also made it possible to increasethe clutch service life by about 1.5times without any significant change inthe operating load over the service life.

The wear adjustment sys-tem of the SAC – con-sisting of the sensor-diaphragm spring(load sensor) andthe deep-drawnsteel adjuster ring –is characterized byvery high functional precision.

Since a harmonic operating loadcurve is required to ensure a comfort-able clutch operation, the SAC wascreated with the capacity to be tunedto specific vehicle characteristic

curves. One of the mechanismsthat makes this possible is the

compensation spring, which can gen-erate the flatter characteristic curvesthat are frequently desired.

The newly developed SAC II providesa further optimization of the system.

Here, the load sensor is not comprised of a second diaphragm spring, butrather of the sensor fingersformed from the main di-aphragm spring and specialtangential leaf springs witha decreasing characteristiccurve.

LuK Clutch DiscsThe clutch disc is the cen-tral connecting element ofthe clutch. Together withthe pressure plate, it disen-

gages and engages the engine fromand with the drive-train.

One charac-teristic of every LuK

clutch disc is its cushiondeflection, tuned to the com-

fort demands of the customer, allow-ing a smooth torque build-up duringdriveaway and an ergonomically tunedpedal effort curve.

The speed and torque fluctuationsgenerated by the combustionprocesses in the engine create noiseand wear in the transmission.

6

1 3 5 7

2000

1000

Actuation Travel [mm]

Forc

e [N

]

conv. Clutch

SAC II for Automatic Clutch

SAC I for Foot ActuationSAC II for Foot Actuation

LuK Clutches

Engage and disen-gage safely and

precisely – proven a million times over.

To reduce these speed fluctuations,the clutch disc must also perform adamping function.

Clutch Discs with Torsion DampersThe clutch disc with torsion damper isthe cost- and space-saving solutionfor torsional vibration problems in thedrivetrain.

The self-centering conical bush devel-oped by LuK compensates possiblemisalignment between the engine andtransmission and also ensures a pre-cise damper function at idle speed.

Clutch Discs without TorsionDampersClutch discs without torsion dampersare used in the most efficient torsiondamping system in existence, the dualmass flywheel (DMFW).

Clutch Discs with MisalignmentCompensationTolerances in the engine and trans-mission, especially with transmissioninput shafts that are not equippedwith pilot bearings, cause a misalign-ment between the crankshaft and thetransmission. In extreme cases to-

gether with rigid clutch discs for theDMFW, this misalignment can lead toidle noise and increased profile wear.

The LuK misalignment compensatingclutch disc, which allows for a dis-placement of the hub in the idle andlow-load range, thus compensatingfor possible radial forces, provides thesolution to this problem, thus guaran-teeing the function of the DMFW at idlespeed even in case of misalignment.

7

Perfection Is Our Strength

LuK Clutches – The Advantages:

Excellent operating comfort

Long service life

Better fuel economy andemission reductions by allowing lower rpms

Low-cost, compact solu-tions through functional integration

Dirt- and corrosion-resistant

Compensation of misalign-ment between the engine

and transmission byclutch discs with mis-alignment compensation

8

LuK Release Systems, LuK Products for Agriculture

LuK Release Systems – system knowledge offers a key advantage.In terms of driving comfort, a driverevaluates the entire clutch and actu-ation system according to smoothdisengagement behaviour, user-friendly force-travel characteristic onthe clutch pedal, silent and vibration-free actuation, together with goodmodulation behaviour during drive-offand shift processes.

The entire system, from pedal to clutch,must function throughout every oper-ating state and guarantee smooth interaction with other vehicle compo-nents. Consideration of the entirechain of functionality requires sub-functions in the clutch system to becarefully tuned to each other.

When the clutch pedal is activated, the driversenses the system’s response. To satisfy requirements on theclutch pedal, clutchsystem componentsmust be tuned in terms offriction, stiffness and mechani-cal advantage of the release system.

Clutch Master CylinderLuK supplies clutch master cylindersin an all-plastic design. These are produced with a number of cross-sec-tional areas and connection geome-tries (bayonet, flange). Due to the selected combination of piston andseal materials and type of lubricantused, these components remain silentduring the actuation process.

Pipe TechnologyUpon request,LuK will under-take both co-

ordination of clutchhydraulic pipe installa-tion and component sup-ply. In addition to the

steel/rubber and plasticpipes currently used in pro-

duction, hydraulic pipe technology is being further developed by LuK in collaboration with our competentpartners.

Anti Vibration Unit and Peak Torque Limiter

Efficient development toolsare used to analyse dynamic

problems and remedial meas-ures prepared with the help of

appropriate simulation models.

One result of such adevelopment isthe so-called “Anti

Vibration Unit”,a pressure differential

valve, which can be used es-pecially to dampen low-frequency

vibrations without additional loss oftravel, thus eliminating unpleasantpedal vibrations.

In the event of the foot slipping sud-denly off the clutch pedal, the clutchcloses abruptly and high loads occurin the drive train. These can be effec-tively avoided if the coupling speed is

Awareness of the latest techno-logical developments allows selection of the best solution.

reduced by using a Peak Torque Lim-iter. This consists of a one way checkvalve installed in the fluid flow path,which only operates during clutch engagement.

Hydraulic Concentric Slave Cylinder(CSC)Hydraulic concentric slave cylinderscombine a number of different func-tions in a compact unit that can beeasily mounted to the gearbox. In or-der to increase the level of functionalintegration (air bleeding, vibrationdamping), LuK makes extensive use ofplastic materials in the design. To min-imise pedal-force, a new lubricant hasbeen developed especially for appli-cation in concentric slave cylinders.This guarantees consistent perform-ance throughout the service life.

Clutch Slave CylinderA development comparable to that for the clutch master cylinders hastaken place in the use of plastics inthe design of external slave cylinders.Similarly to the concentric slave cylinders, it is possible to integrateadditional functions.

LuK Release Systems – The Advantages:

High level of vehicle competence

Component design using knowledge of the entireclutch and actuation system

Minimal vibration, noise and friction

Innovative design solutions using plastic materials

9

The Right Move From The Start

LuK Products for Agriculture –It Is Good to Have a Wide Field of Application Options.Farmers all over the world work tofeed mankind. The farming machineryindustry supplies them with powerful,reliable tools with which to do the job.As a long-time partner of farm machin-ery manufacturers, LuK makes an im-portant contribution.

The one indispensable tool of thefarmer is the tractor. Originally noth-ing but a steel draft animal, it has developed over its hundred-year his-tory into a universal drive machine: a pulling machinefor tilling the fields and trans-portation, a drive machineand carrier for a number ofdifferent types of equipment,a provider of mechanical,electrical or hydraulic energy.The operating conditions

Torsion Dampers to Link the Engineand TransmissionCombustion processes in the enginecreate speed and torque fluctuations.These fluctuations cause noise andtransmission wear. Torsion dampersare used to reduce these fluctuations.

LuK supplies torsiondampers with linearor curved compres-sion springs. Theycan be open and rundry or closed and lubricated. They are

used in mainand auxiliarydrives fortorque ranges of 100 to 2000 Nm.

Release Bearings and Release Systems for TractorClutchesLuK supplies mechanical andhydraulic release bearings andrelease systems for agriculture.They are used in conjunctionwith single- or double-clutches.

Other LuK products are also suitablefor the agriculture field.

change from user to user, country tocountry and continent to continent.

Knowledge of the requirements associ-ated with these conditions, careful development of suitable products andproduction shops on five continentshave made LuK the world’s marketleader in clutches for agriculturalequipment.

Dry Friction ClutchesDry friction clutches, in the form ofsingle-, double- or multi-disc clutches,are used both in main and auxiliary

drives. LuK sup-plies frictionclutches forpower outputranges between20 and 180 kWwith diametersfrom 225 to 360 mm.

LuK Products for Agriculture – The Advantages:

As a partner to the farming equipment industry, LuK offers

Expertise

Customized solutions

Coverage of the entire performance spectrum

A global presence

Two separate LuK PSGclutch actuators ensure precise controlof the twin clutch. Depending on theapplication, the twin clutches can eitherbe dry or wet (running in oil). Actuationis either electro-mechanical or electro-hydraulic.

LuK ESG ComponentsBuilding on the PSG, the LuK ESG com-ponents allow a hybrid concept, inwhich a starter generator is linked toone of the gearbox input shafts. Advantages of the ESG include func-tions such as start/stop, energy recu-peration by regenerative braking andelectric powered driving, all with acompact design. Furthermore, with the

Increasing traffic density means a grow-ing demand for systems to relieve driv-ers of more ”routine tasks“. Today, autoshift gearboxes and twin clutch gear-boxes provide alternatives to conven-tional automated transmission solu-tions, offering particular benefits interms of fuel consumption and dynamicperformance. Together, these gearboxvariants are known as the ”XSG Family“

LuK is developing components for usewith the XSG Family. These space-sav-ing, robust units will be available for allkinds of applications in the future.

LuK ASG ComponentsComponents for the automated shiftgearbox, known as the LuK ASG, formthe technical basis of the XSG Family:three electric motors perform the move-ments that the driver would otherwiseactivate with the clutch pedal and gearlever. The gearbox itself remains unal-tered and the required components areboth compact and low in weight.

For added comfort, a gearbox with LuKASG components offers the

option of manual or auto-matic gear shifting.

In manual oper-ation, gear

changing is triggered electronically bytouching the gear lever or other con-trols. In automatic mode, shift pointsare set by the control unit dependingon the driving situation. It is possibleto switch between the operating modesat any time and the system also allowsany gear shift pattern.

The LuK ASG gear control is either inte-grated in the gearbox or connected tothe exterior gearbox control. Clutch ac-tuation occurs via an electro-mechani-cal drive mechanism, which can moveand hold the clutch across the totalrange of clutch travel. Thanks to a self-adjusting clutch (LuK SAC), clutch actu-ation is both dynamic and efficient.

Due to optimised shifting characteris-tics, LuK ASG components can reducefuel consumption compared to a man-ual gearbox, which canmean savings of morethan 10% in the Euro-pean consumption cycle.

LuK PSG ComponentsThe PSG is a twin clutchgearbox, consisting oftwo gearbox units divid-ed into even and oddgears, and a twin clutch.During gear shifting, the torque is transferredsmoothly from oneclutch to the other. Thisresults in excellent shiftcomfort comparablewith that of a conven-tional automatic trans-mission, but with thesame low fuel consump-tion as ASG.

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LuK XSG Family: Gearbox Automation

Driving pleasure comes automatically. Without using a clutch or shifting gears.

• Brushless Motors:Extremely dynamic applications requiremotor technology which, in addition tolow packaging space requirements andhigh performance, is also characterisedby low inertia. Brushless motors offerall these properties, combined withhigh reliability.

Specially optimised brushless motorsare being developed for application inthe LuK XSG Family components.

• Modular Actuation:LuK components for the XSG Familycan be used for various functions.

For example, hydrostatic clutch actua-tion can be used for ASG and PSG applications; and indeed for both wetand dry twin clutches on the PSG.

The base unit of the gearbox actuationwith a central shift shaft can be usedequally for both ASG and PSG. Only theflange and shift shaft are specific tothe gearbox.

• Software Development:In addition to the components, LuKsupplies a control software module upto and including the entire system. The entire system's behaviour can beadapted by the vehicle manufacturerfor their respective application via asoftware interface.

Particular highlights of the software include slip control and anti-juddercontrol. Both functions ensure lasting,superb driving comfort with LuK clutchactuation.

combustion engineswitched off, the air-conditioning systemcan be operated usingthe electric motor.

Depending on the application, the ESG

can result in reduced fuel consumption of over

20% compared to a manualgearbox.

Technical Highlights ofthe LuK XSG Components• Active Interlock:This new gearbox actuation

principle separates the mechanical ele-ments for engagement and disengage-ment of gears. The shift finger can bemoved into the next position while a

gear is engaged and the clutch stillclosed. The old gear is then disen-gaged and the new one engaged inone single motion, whilst interlockingof gears is ensured in all situations.Shift times are largely independent of which gear change is to be per-formed. Hence shifting across severalgears on automated gearboxes withActive Interlock is almost as fast as asimple gear shift without changing the gear slot.

The LuK ASG gear actuator with ActiveInterlock reduces shift times withoutadversely affecting comfort and wear.

With Active Interlock applied to theLuK PSG gear actuator, only one singleunit with two electric motors is neededto actuate both gearbox units.

11

Enjoy Relaxed Driving

More relaxed driving

Low weight

Flexible interior designdue to shift-by-wire

LuK XSG Family – The Advantages:

No clutch pedal

Comfortable automatic mode

Sports manual mode

Fuel-saving

In 1999 LuK became the first systemsupplier to introduce CVT componentsfor torque ranges of 300 Nm andabove and put them into production.Together with high-performance engines, these components have rede-fined the concepts of dynamics andcomfort with excellent fuel-consump-tion figures.

The CVT PrincipleContinuously variable gear ratiochanging is achieved in the chain CVT,which is suitable for passenger car applications, by varying the axial spac-ing of the cone-shaped pulleys on theshaft. The chain can run between thetwo conical pulleys at different radii.The power transmission occurs solelyvia friction in the steel/steel contactlubricated with oil.

LuK Solutions Provide Breakthrough: Two-Stage Hydro-MechanicalTorque SensorToo little clamping pressure betweenthe cone-shaped pulleys and the chaincauses the chain to slip. Too muchclamping pressure puts too much loadon the components and reduces theefficiency of the system through unnec-essarily high friction losses. LuK’s two-stage hydro-mechanical torque sensorensures the right clamping pressurefor the specific driving situation.

The torque is inducedusing a ramp plate,through which thepower flows by meansof ball bearings to an axially moveablesensor piston sup-ported by oil pres-sure. The oil coming

from the pump flows out through avariable discharge bore, which en-sures constant equilibrium betweenthe axial force of the ball ramps andthe compressive force. In the event of a sudden change in torque, thetorque sensor temporarily acts as apump, able to deliver a flow of morethan 30 l/min, thus causing a veryrapid pressure increase.

The LuK Dual-Piston PrincipleThe demands on the hydraulic adjust-ment system of the variator are very high.Fast controls requirehigh pump power out-put in conventional CVTsystems. The LuK dual-piston principle reducesthe volumetric flow required to operate theadjusting cylinder to athird of that required byconventional systems.

The hydraulic oil ismoved directly from onepulley to the other athigh pressure withoutrequiring additional energy. This means thatthe pump can be de-signed considerablysmaller, which improves

the overall transmission efficiencyand thus the fuel consumption andperformance.

LuK ChainExisting chains could not reliablytransmit and withstand torquesabove 200 Nm. LuK has therefore developed a special rocker pin chain, which can transmit torques of up to 400 Nm for high-perform-ance automotive applications.

It is constructed of various link plates,which are joined together by therocker pins of the links. This chain al-lows a wide gear ratio spread withhigh torque capacity. Low internalfriction losses ensure high transmis-sion efficiency. The combination ofthe chain and the curved, conical pul-leys provides excellent adjustment

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LuK CVT (Continuously Variable Transmission)

One Step Further with Continu-ously Variable Gear Ratios.

Primary Pulley Set with LuK Double Piston

Secundary Pulley Set with LuK Double Piston

dynamics. In addition, the chain isimmune to track offset angle. Enhanced acoustic performance wasachieved by computer-aided optimization of the link plate pitchsequence.

Compact Hydraulic SystemThe compact hydraulic system, alsosupplied by LuK, with its direct flangepump, performs all of the controlfunctions required in the transmis-sion. More specifically, these includedelivering the oil for the clampingforce and variator adjustment, for thestart up element and for cooling and lubrication. The compact design,configured for high control pressuresof over 60 bar and newly developedcontrol technology, represents the realization of an ideal transmissionsolution.

13

Experience Driving Dynamics Again

LuK CVT (Continuously Variable Transmission) – The Advantages:

Increased driving comfort

Smooth transmission ratio changes

Low fuel consumption

Fewer components than in steppedtransmissions

Excellent driving dynamics

Compact design/smaller packagingspace

LuK Torque Converters – Advantage through Optimization

The torque converter has been usedfor decades now as a start-up andtorque-transmitting device in automat-ic transmissions. Forecasts show that

the torque converter willnot be completelysqueezed out by alternative concepts

in the future if develop-ment of the ex-

isting convert-er and gearbox

system is con-tinued con-sistently.

MinimizingSlip

Since the torqueconverter’s operating principle requiresslip in order for it to be able to transfertorque, its operation is always associ-ated with dissipated energy.

What would then be ideal is to utilizethe advantages of the torque converterfor launch and then immediately closethe lock-up clutch while driving. In orderto prevent noise or vibrations from occurring, LuK sells specially tuned high-performance torque dampers that havebeen produced in the millions and min-imize the existing vibrations throughtargeted damping and tuning of thespring gradients.

Use of a LuK turbine torsion damper,which eliminates special vibration conditions, particularly with a standarddrive, can provide an even earlier lock-up with respect to conventionaldampers without sacrificing comfort.

Controlled Operation withLow SlipAnother option for preventing vibra-tions is controlled operation with lowslip. For this approach, LuK supplies innovative friction facing cooling tech-nologies to minimize vibration. Thesetechnologies rise above the competi-tion due to their long service life andextreme cooling capacity. These tech-nologies allow for simpler designswhile at the same time using inexpen-sive standard facings. Another positiveside effect is a longer life for gear oil,which can be very advantageous withtoday’s high-load transmissions.

In the area of NVH reduction, LuK canmake use of decades of drivetrain experience with precision simulationtechniques, which can significantlyshorten project realization times.

Optimizing the Fluid CircuitTo optimize the fluid circuit, LuK uses3D flow simulation programs through-out development to make it possible toprecisely predict the Torque convertercharacteristics early on. This also allowsfor reduced installation space andmass moment of inertia with the sameTorque converter performance, or for amore fuel-saving torque converter de-sign with the same installation space,as compared to competitors’ products.

All in all, LuK offers an innovative andflexible, customizable torque converter

package for automatic transmissions,which clearly shows that when inno-vations are implemented logically, performance improvements are stillpossible even with systems that ap-pear technically exhausted.

Internal Crankshaft Damper – Reducing Torsional Vibrations on the CrankshaftThe natural frequency of the crank-shaft is excited when running a com-bustion engine, due to the gas and inertial forces. This causes the twoends of the crankshaft to twist stronglyagainst one another, which can causenoise and torsional fractures of thecrankshaft.

To reduce the load on the crankshaft,torsional vibration dampers are gener-ally used today, inte-grated with the beltpulley of the acces-sory drive at the freeend of the crankshaft.

Some next-generationengines will eliminatethe belt drive, drivingthe accessories byother means, butstill requiring thetorsional vibra-tion damper.

LuK’s idea wasto integrate thedampers intothe crank web with

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Torque Converter, Crankshaft Damper, Belt-Driven Starter Generator

Go Further with Robust Systems and Less Fuel.

LuK Torque Converters – The Advantages:

High hydrodynamic efficiency

Earlier lock-up with an innovative damper

Possible use of turbine torsion dampers

New, better-performing facing cooling concepts

as little effect as possible on the spacerequirements. The tight space condi-tions associated with this solution allow only a low moment of inertia forthe vibrating masses. A sufficient reduction of the torsional vibrations of the crankshaft is possible only byusing steel compression springs whosehigh energy absorption capacity per-mits large vibration angles.

Belt-Driven Starter Generator(RSG) – Now Stop-and-Go TrafficSaves FuelThe use of a starter generator makescomfortable start-stop operation of a combustion engine possible. To do this, it shuts off the engine atstandstill and starts it automaticallywhen the gas pedal is pressed again. This start-stop operation of the enginecan reduce fuel consumption in the city by about 5%, depending onthe engine.

The belt-driven starter generator(RSG) is advantageous here becauseof its simple design. This conceptmakes it possible to use known andthus proven components and also allows it to be combined with any

transmission without any modifica-tions to the drive train.

The belt’s gear ratio (2.5 – 3), however,is insufficient for reliable starting ofdiesel engines and larger gasoline en-gines, especially at low temperatures.

For this reason, LuKhas developed acompact two-speedgearbox that allows a higher total gearratio (e.g. 6 – 7). The gearbox is inte-grated within thecrankshaft pulley and, in addition to providingthe start-up gear ratio, it effectively decouples the accessoriesfrom the vibrations of the crankshaftusing a free wheel. To drive acces-sories while the engine is off, the LuKgearbox can be shifted into neutralwith a simple actuator.

15

Expand Your Radius

Belt-Driven Starter Generator (RSG) – The Advantages:

Start-stop operation reduces fuelconsumption

Lower development expenditures

Low system cost

No additional weight

Favorable installation spacerequirements

Accessory free wheel decouples vibrations

Accessories can be drivenwhile engine is off

Internal Crankshaft Damper – The Advantages:

Reduced crankshaft load

Reduced engine noise

Space advantages

Reduced engine mass

LuK Power Steering, Chassisand Transmission PumpsIn response to consumer demand, the current trends in automotive design are driven towards increasedcomfort, driving pleasure and im-proved fuel economy. What is requiredto reduce steering effort is a lightsteering control that conveys a pre-cise driving feel. Drivers want a firm,sporty chassis for cornering and braking, but without unnecessaryharshness in everyday use.The trans-mission should shift automaticallyand conserve energy.

LuK power steering pumps for pas-senger cars and trucks meet customerrequirements for hydraulic powersteering systems. The vane pumps aremodified and tuned to the operatingconditions.

By using the energy saving pumpLF30EV2, the pump's energy con-sumption can be reduced by up to50%.

The power steering pump can be combined with other pumps into

tandem pumps (see page 18). A second vane part could be addedfor diesel supply or designed as a vacuum pump.

Alternatively, a radial piston pumppart could supply pressurised oil atup to 200 bar to suspension-struts on chassis systems with anti-roll andpitch suspension adaptation as re-quired. Firm handling when braking

and cornering is thus achieved withan otherwise comfortable chassis andsuspension set-up.

Vane pumps for transmission appli-cations provide pressurised oil for adjusting and controlling automatictransmissions with variable gear ratios, making it possible to alwaysdrive with the correct gear ratio, thussaving energy.

16

LuK Power Steering, Chassis and Transmission Pumps, CO2 Air Conditioning System

Totally Calm – Even on Tricky Bends.

Low Pressure Area

High Pressure Area

Contour Ring

Rotor

Vane

LuK Power Steering, Chassis and Trans-mission Pumps – The Advantages:

Increased efficiency

Low power consump-tion

Compact dimensions

Long service life

Low noise level

17

CO2 Air Conditioning SystemAutomotive air conditioning systemsmake a significant contribution both tocomfort and passive safety. Studiesshow that the ability to concentrate decreases significantly at interior tem-peratures above just 25°C. As with power steering before it, air condition-ing will continue in its application all the way to the compact car class in theyears to come.

Only non-combustible coolants areused for climate control in automotiveair conditioning systems. Otherwise,small amounts entering the passengercompartment could become a potentialexplosion hazard. After R12 was bannedover 10 years ago due to its high globalwarming potential, there is now a grow-

Cool And Collected – And Safe On The Road

ing movement calling for a ban onR134a. Research has unearthed acoolant for use in automotive air condi-tioning systems that are among the old-est coolants of all: CO2.

In addition to the environmentalbenefits, the technical advan-tages of this new coolanthave increased in importance over time.CO2 air conditioningsystems consume 20%less fuel than today’s sys-tems due to their betteraverage efficiencythroughout the year.

The cooling capacity of today’s air con-ditioning systems is limited by the com-

pressor piston displacement. Greaterpiston displacement is not possible, because there is insufficient space for asuitable compressor in the engine com-partment. CO2 air conditioning systemsonly need about 13% of the volume flowof an R134a system. This makes it possi-ble to use smaller compressors, whichenable the CO2 system to cool the pas-senger compartment noticeably fasterthan today’s systems.

Because the process is also reversible,unlike today’s air conditioners, it alsohas a heat pump function. This can beused to heat up the vehicle interior veryquickly, replacing the electric supple-mental heaters

that are common with modern

direct-injection diesel engines.

LuK has specialised in the development of coolant compressorsand put its pump expertise into practicewith the new technology.

It is predicted that the clear tech-nical advantages of the CO2 tech-nology will begin to replace to-day’s conventional airconditioners starting in 2007.

The manufacture of the first stan-dard production applications is currently in preparation.

LuK CO2 Compressors – The Advantages:

Excellent coolingperformance

Excellent control be-haviour

Drag losses 50% less than with R134a compressors

Integrated pressure relief function for the entire system

Excellent isentropicefficiency (>75%)

Suitable for highmaximum pressures

and high tempera-tures

Heat pump functionpossible withoutmajor additionalexpense

Developed in cooporation with Sanden Corporation

Because of the many requirementsthat modern vehicle engines place onthe auxiliaries they run, LuK has exclusively used the rotating vane celloperating principle from the begin-ning. This concept has spread through-out the world as the only pump designstill in use today.

LuK Vacuum PumpsLuK’s complete redevelopment of thevane cell principle finally led to theuse of the world’s first single-vanepump in standard production in 1995.This pump, type VAPEC S, is made upof very few individual parts and com-bines a compact, low-weight size witha high flow rate, low oil flow rate andminimal power consumption.

Vacuum pumps are made in sizes of70, 140, 190, 230 and even 270 cm3, thus covering the entire spec-trum of the suction power require-ments of modern vehicles, from sub-compacts to light commercial trucks.The VAPEC S can expediently providethe higher flow rates required up to

now for larger and heavier vehicles inconjunction with high amplifier volumes.

While the use of vacuum pumps was initially limited to diesel engines,today LuK manufactures the latestvacuum pumps for use with gasolineengines with infinitely variablecamshaft adjustment or direct injection.

LuK Tandem PumpsLuK’s outstanding position as a makerof other auxiliary units, such as powersteering pumps, fuel pumps and oilpumps, etc., (see page 16) also helpsin cases where a solo vacuum pumpcannot be installed or would be veryexpensive to install.

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LuK Vacuum and Tandem Pumps

Good Form and Extremely Durable.

VAPEC S-packaging volume

26,5

Oil inlet

Packaging-Advantages:

Extremely compact in axial direction:26,5 mm (VAPEC 14 S)

Air and oil outlet integrated in thecentering diameter:advantageous for the cylinder head design

Overall length

VAPEC 14 S: 26,5 mm

VAPEC 19 S: 35,0 mm

VAPEC 23 S: 45,0 mm

Oil and air outlet

Air inlet

Ø 5

0 g7

For such cases, LuK offers tandempumps, which can consist of a combi-nation of a vacuum pump with a powersteering pump, fuel pump or otherauxiliary units, as a solution.

One example of such a tandem pumpis the combination of a single-vanevacuum pump with a fuel pre-supplypump manufactured for use withdiesel engines with pump nozzle injec-tion technology.

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An Example Of Power

Sturdy construction with highdurability and cold-startingability as well as low idle noise

Very small outside dimensionseven with high flow rates

Outside dimensions can be adjusted to installation conditions

Low weight

Low engine lubricating oil flow

LuK Vacuum and Tandem Pumps – The Advantages:

High suction power to coverthe requirements of existingspecifications

Extremely low power consump-tion, which contributes in turnto reduced fuel consumption

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Thinking Ahead.

Thinking ahead does not simply meanencompassing innovation and qualityfor their own sake, but treating the finite resources of our environmentcarefully and responsibly. Thinkingahead also means recognising that innovation and quality are key ele-ments of a car’s fascination and, assuch, evoke enthusiasm in motorists.

Motivated by ExcellenceAwards are grounds for both pleasureand motivation. We are particularlypleased that our customers consis-tently award us for quality, service,technology, price and overall perform-ance. These factors form the basis ofthe LuK quality policy, which is under-pinned by the individual responsibilityassigned to every employee.

Quality AwarenessQuality assurance starts right at theearly stages of a project.

Following proven planning methods,product requirements are assessedjointly with the customer and any risksminimised via the design process. FE-calculations and prototype pro-grammes support the decision-makingprocess. Internally developed test sta-tions reflect our many years of productexperience and guarantee a constantlevel of quality across all sites.

The specialist knowledge of our col-leagues in manufacturing equips themto independently approve processesand products. In so doing, they applythe standardised test specifications as required.

Extensive process documentationforms a basis for continuous improve-ment. Our flat decision-making structure means this development isnot only rapid, but also benefits our customers.

Know-how – with a Conscience!LuK employees think ahead. This doesnot just apply to quality, but also inour responsibility towards the environ-ment. LuK uses the most modern tech-nology and processes for even greaterprotection of natural resources, reduc-tion of noise, emissions, water usage,waste and scrap. LuK’s fundamentalenvironmental principles contributetowards a heightened awareness ofresponsibility for the environment atall levels throughout the company.

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Used clutches from both cars andcommercial vehicle have beenprocessed since 1976; since 2001 this also applies to power steeringpumps. As such, LuK has shown itself to be a pioneer in this field.

Because ...It concerns us all!

This thought process starts duringproduct development. New productsshould be as effective in saving resources as possible and be capableof being recycled at a later date. The process ends with the collectionand recycling of used products.

All LuK sites are certified in accordancewith ISO 14001.

Ideas for tomorrow’s automotiveworldWhilst technological progress is basedon knowledge, it is ideas that are behind every product innovation. LuKtherefore rates development highlyand one sixth of its total workforce isinvolved in development work.

Our attention is focused on customers,their projects and their future visionfor tomorrow’s automotive world. Anindividual project team is allocated for each project and will take care oftransforming their requirements – in asimple and straightforward way.

Customer expertise and LuK’s special-ist knowledge enable us to act as atrigger for numerous developmentswhich make the car safer, more com-fortable and more economical.

It is also an integral part of LuK’s philos-ophy to constantly offer customersnew ideas and suggestions, thus act-ing as a specialist “think-tank”. This ishow, together with customers, manyimportant chapters have been writtenin automotive technology history:

starting with the first high volumemanufacturing of a diaphragm springthrough the invention of the dual massflywheel to the components for thefirst high-performance CVT, with torqueranges of over 300 Nm and, in powertake-off configuration, even up to 500 Nm.And these are just a few examples.

We will continue to devote ourselvesto backing sound, forward-lookingideas and consistently transformingcustomers’ requirements into reality.Robustness and reliability must there-fore be key benchmarks of every tech-nical solution. After all, a motorist’sfascination with technology is only fuelled by a combination of innovationand reliability. It is this combinationwhich bonds him to his make of carand confirms that he has chosen theright product.

It is this which makes the complex andall-encompassing thought process,and hence the development of knowl-edge synergies so important. Thinkingsystems – that is our benchmark,whether in the field of release systems,where we develop completely newtechnical solutions through the con-sistent transformation of the “clutchand control” system idea, or in thefield of CVT. Our work here is not onlybased on our knowledge of CVT com-ponents, but also on the know-how of the combined function of the chain

variator, start-up element, hydraulics,software and entire vehicle, as well as LuK specific development and simu-lation tools.

An efficient test rig and laboratory in-frastructure is available both for com-ponent testing and material researchand development. State-of-the-artCAD and FEM programs with internallydeveloped simulation and calculationmodules, flexible

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Our most important awards come from enthusiastic motorists.

prototype manufacture supported byextensive measurement and test trackactivities, together with a sophisti-cated process development that stan-dardises manufacturing, assembly,test and logistic processes, all com-

bine to ensure that innovations aretransformed into products of the high-est quality.

What can we do for you?

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LuK GmbH & Co. oHGIndustriestrasse 3D-77815 Bühl/BadenTelephone: +49 7223 941-0Fax: +49 7223 26950www.LuK.com S

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