Double Cone Synchronizer with Paper Lining for Medium Duty Trucks 902278
A new transmission using a double cone synchronizer with paper lining is mounted in Hino's new medium duty trucks “Cruising Ranger”. The shift force and the shift feeling of these trucks have been improved by the high capacity of double cone synchronizer and the superior friction property of paper lining.
In this paper the characteristics of this system are compared with other types of synchronizers and several kinds of friction materials, concerning performance and durability. The result shows the advantage of synchronizing and second bump performance of double cone synchronizer with paper linings. The result of durability testing shows that paper lining has superb wear properties and stable friction coefficient, which are factors that prove the double cone system has sufficient durability.
IN ADDITION to fundamental performance factors such as engine power and fuel consumption, comfort and easy operation are other factors that, have become increasingly important in recent years to drivers of Heavy and Medium-Duty trucks. However, despite the need for lighter, smoother and more reliable shifting, the transmission is becoming harder to operate due to increased loads on the mechanism caused by larger engine power and increased inertia due to clutch size and transmission size.
Under the circumstances, a transmission incorporating a multi-cone synchronizer with a substantially higher capacity has been developed and put into use (1)*. The reliability of multi-cone synchronizer when used with heavy and medium duty trucks under severe load conditions must be ensured.
This paper describes the Hino's new type synchronizer which is constructed of a double cone synchronizer combined with a paper friction material. This has been developed for Hino medium duty trucks and has provided remarkable improvements in performance and reliability.