Design of Synchronizer
Keywords:
synchronizer, coefficient of friction, synchronizer size, index torque, cone torque, Chamfer Angle.Abstract
Today, synchronizers are used in all manual transmissions including trucks and commercial vehicles. Most
synchronizing systems are patented or covered under copyright act. Little technical information is available in public
domain.The manual transmission synchronizer design has been a real challenge and is usually referred to as a myth and
black magic. A mathematical algorithm and dimensioning and tolerancing scheme has been developed to dispel this
myth. The paper attempts to demonstrate the fact that the calculations of synchronizer physical parameters should be
supported by Sopacticated dimensioning and tolerancing the components design to achieve the intended functional
objective. A mathematical algorithm is developed which facilitates establishing the sleeve and blocker ring pointing
angle relationship with the synchronizer size, coefficient of friction, cone torque, and index torque. The relationship is
presented graphically in a unique manner identifying the clash and hard shift zones. As such, it allows sizing the
synchronizer and selection of the parameters for a given application for comfortable shift ability between the two
extremes of clash and hard shift.
