The emergence of new technology of fuel efficient dual clutch, electronically shifted, automatic transmissions employs conventional manual transmission architecture where synchronizers play a major role of precise gear shifting. Although shift quality is not directly affected by the synchronizers, smooth and quick transition of gears, including upshift, downshift, and skip shift is logically a significant factor in accomplishing the fuel economy objective.DCT design with dry clutches is feasible in low torque applications with manageable thermal capacity and clutch wear, whereas wet clutches are used in high torque applications that can manage heat with cooling. The synchronizer design is critical in both applications substantially affected by system efficiency including clutch drag, bearing frictional losses, and fluid churning losses, plus energy losses due to friction and deflection in shift and clutch actuation mechanism. Hence synchronizer design must satisfy the following two major demands: The above requirements establish the boundary limits for index torque to be smaller than synchronization torque and greater than total transmission drag.Increasing index torque by reducing the pointing angle to compensate for clutch drag and total transmission losses could conceivably require increasing synchronization torque by increasing cone coefficient of friction to safeguard (gear shift) against clash.The relationship of above significant parameters for smooth gear transition is mathematically established and experimentally verified. Synchronization torque measurement procedure is known, but index torque is usually not measured. For verification purposes a measurement method was formulated and a fixture was built accordingly. Calculated and measured drag torque values were observed to have good correlation with coefficient of friction between sleeve and ring chamfer surfaces as variable.The test results manifest that in a dual clutch transmission precise and quick shifting is elemental to the function of the transmission, and system efficiency is fundamental to both fuel efficiency and synchronizer function.


    Zugriff

    Zugriff prüfen

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Synchronizer Design and Development for Dual Clutch Transmission (DCT)


    Weitere Titelangaben:

    Sae Technical Papers


    Beteiligte:

    Kongress:

    SAE World Congress & Exhibition ; 2007



    Erscheinungsdatum :

    16.04.2007




    Medientyp :

    Aufsatz (Konferenz)


    Format :

    Print


    Sprache :

    Englisch




    Synchronizer design and development for dual clutch transmission ( DCT )

    Razzacki,S.T. / Hottenstein,J.E. / Daimler,Stuttgart,DE et al. | Kraftfahrwesen | 2007


    Synchronizer Design and Development for Dual Clutch Transmission (DCT)

    Razzacki, S. T. / Hottenstein, J. E. / Society of Automotive Engineers | British Library Conference Proceedings | 2007


    2007-01-0114 Synchronizer Design and Development for Dual Clutch Transmission (DCT)

    Razzacki, S. T. / Hottenstein, J. E. / Society of Automotive Engineers | British Library Conference Proceedings | 2007


    A New Control Strategy of Wet Dual Clutch Transmission (DCT) Clutch and Synchronizer for Seamless Gear Preselect

    Adhitya, M. / Mustafa, R. / Plotner, A. et al. | British Library Conference Proceedings | 2013


    Clutch with synchronizer and locking mechanism

    SPELLER CHARLES HUBERT | Europäisches Patentamt | 2021

    Freier Zugriff