5th Jun 2007 07:03
Torotrak PLC05 June 2007 Torotrak and Xtrac transmission expertise will help F1 teams develop new, highly efficient, mechanical kinetic energy recovery systems ... technology also applicable to road cars 5 June 2007 Toroidal traction drive specialist Torotrak plc and vehicle transmission designand manufacturing company Xtrac Ltd are pleased to announce that on 4 June 2007they entered into a licence agreement to enable Xtrac to develop highlyefficient and compact continuously variable transmissions (CVTs) for use in thenew kinetic energy recovery systems (KERS) proposed for Formula One ("F1") motorracing. In 2009, F1 is introducing new rules that will lower the environmental impact ofthe sport. Part of this is to recover deceleration energy that can be stored foracceleration. Xtrac will exploit Torotrak's full-toroidal traction drivetechnology for use in kinetic energy recovery systems within the motorsportindustry, to assist its customers in meeting these new obligations. Commenting on the co-operation between the two companies, Peter Digby, managingdirector of Xtrac, said: "The transfer of world-class transmission technologyfrom Torotrak, combined with the added value of Xtrac's expertise in the designand manufacture of transmissions for motorsport - and with clear potential tofeed the resulting technical solution back into mainstream automotive use - is agood example of what I believe FIA President Max Mosley had in mind when heannounced that Formula One should embrace an energy efficient future and open upthe world of motorsport to new manufacturers". Dick Elsy, Chief Executive at Torotrak, added: "We are delighted to be workingwith Xtrac on this exciting new application of our transmission technology, toprovide a highly efficient KERS solution for initial application in motorsport,but with a clear opportunity to apply the system in mainstream road cars toprovide performance, economy and greenhouse gas emission benefits." Background Some of the new KERS systems under development will be mechanically based andwill utilise a flywheel to recuperate, store and subsequently discharge a movingvehicle's kinetic energy, which is otherwise wasted when the vehicle isdecelerated. The kinetic energy is stored during a braking manoeuvre and is thenreleased back into the driveline as the vehicle accelerates. The toroidal traction drive variator, being developed with Torotrak and usingTorotrak's patented technology, is a central element in these mechanicalflywheel-variator KERS systems as it provides a continuously variable ratioconnection between the flywheel and the vehicle driveline, via the vehicle'sgearbox. Torotrak has granted a licence to Xtrac to design, manufacture,assemble and distribute components or complete variator systems, whichincorporate Torotrak's technology, to its F1 customers. The innovative combination of a Torotrak variator - providing mechanicalefficiency that should be in excess of 90 per cent - with a flywheel of advancedconstruction, results in a highly efficient and compact energy storage system.Whilst Xtrac will supply variator units to its customers, the flywheels forthese energy recovery systems are being developed separately by the Formula 1teams themselves and their specialist suppliers. Torotrak will provide thecontrol system expertise. Torotrak and Xtrac believe that the variator-flywheel solution provides asignificantly more compact, efficient, lighter and environmentally-friendlysolution than the traditional alternative of electrical-battery systems. "The variator weighs less than 5kg in these applications and provides a highlevel of mechanical efficiency, enabling the overall mass of the mechanical KERSsystems to be minimised," says Chris Greenwood, technology director at Torotrak."This mechanical efficiency, combined with the variator's ability to changeratio very rapidly, helps to optimise flywheel performance." The two companies consider that the system is applicable to other motor sportsand everyday vehicles and see the potential for wider applications -particularly on high-performance road cars - as an aid to performance and alsoas a means of developing future products with reduced CO2 emission levels. The system supports the current trend in powertrain design for enginedownsizing, by providing a means of boosting acceleration, overall performanceand economy independently of the vehicle's engine and without the need forcomplex electrical-battery hybrid architectures. A CVT-controlled flywheel is particularly suited to stop-start drivingsituations when real-world fuel economy is often at its worst. In theseconditions, the variator-flywheel system can assist the launch of a vehiclewhich has slowed down or come to a standstill, by utilising the kinetic energystored in the flywheel. In heavily congested traffic, where a car is frequentlystopped and restarted, the system can help alleviate the heavy fuel consumptionand emissions of greenhouse gasses normally associated with these conditions. For the F1 applications, the stored kinetic energy can be applied by the driveron demand whenever required - at a rate and for a time period set by theregulations - to boost performance for rapid acceleration. The device isparticularly beneficial when exiting corners or for tricky overtakingmanoeuvres. "The mechanical efficiency, compactness and mass of the variator system iscritical since it directly influences the size and the ability to package suchas system into an F1 car, or into a road vehicle," says Adrian Moore, technicaldirector at Xtrac. "The size, torque capacity and response of the unit iscritical to take the full advantage of having a flywheel KERS system." Contact: Torotrak Lulu Bridges / Simon HudsonTavistock CommunicationsTel: 020 7920 3150 www.torotrak.com Xtrac Rob Palmer, media communications,Tel: +44 (0) 1582 763255 Email: [email protected] Note to editors Torotrak is a world leader in the development of full-toroidal traction drivetechnology for use in automotive, truck, bus, off-highway and ancillary drivemarkets. Xtrac specialises in vehicle transmission technology focussed on clients in theaerospace, automotive, defence, marine and motorsport sectors. Technical notes on Torotrak's toroidal variable drive technology The components within each variator include an input disc and an opposing outputdisc. Each disc is formed so that the gap created between the discs is'doughnut' shaped; that is, the toroidal surfaces on each disc form the toroidalcavity. Two or three rollers are located inside each toroidal cavity and are positionedso that the outer edge of each roller is in contact with the toroidal surfacesof the input disc and output disc. As the input disc rotates, power is transferred via the rollers to the outputdisc, which rotates in the opposite direction to the input disc. The angle of the roller determines the ratio of the Variator and therefore achange in the angle of the roller results in a change in the ratio. So, with theroller at a small radius (near the centre) on the input disc and at a largeradius (near the edge) on the output disc the Variator produces a "low" ratio.Moving the roller across the discs to a large radius at the input disc andcorresponding low radius at the output produces the "high" ratio and providesthe full ratio sweep in a smooth, continuous manner. The transfer of power through the contacting surfaces of the discs and rollerstakes place via a microscopic film of specially developed long-molecule tractionfluid. This fluid separates the rolling surfaces of the discs and rollers attheir contact points. The input and output discs are clamped together within each variator unit. Thetraction fluid in the contact points between the discs and rollers become highlyviscous under this clamping pressure, increasing its 'stickiness' and creatingan efficient mechanism for transferring power between the rotating discs androllers. This information is provided by RNS The company news service from the London Stock ExchangeRelated Shares:
Torotrak PLC