Gear change mechanism for heavy tractor etc. - has two layshafts, hydraulic torque converter, and friction and dog clutches in parallel mechanical and hydromechanical gear trains

摘要

The gear change mechanism comprises two friction clutches (2,4), an output shaft (8) with gear wheels, one or tow lay layshafts (6) with gear wheels and dog clutches (7). A hydraulic torque converter (3) an overriding clutch (9), and control elements complete the assembly. It comprises a purely mechanical gear train (1,4-8) with one or moe gear ratios (I,II), arranged parallel to a hydro-mechanical gear train with one or more gear ratios. A part of the mechanism provides the gear change via the dog clutches, whilst a friction clutch (2) is arranged between the mechnical train and the input shaft (1) on one or the other side of the converter. The torque converter pref. has a turbine runner wheel (T) coupled to output part by the overriding clutch. ADVANTAGE - Min power loss and wear of the gear shift elements, while permitting gear changing under load.