Technical Paper
A “Back-to-Back” Comparison of Currently Available Hydromechanical Transmissions – Utilising Boeing Easy 5™ Mathematical Modelling with the Ricardo Powertrain Library
1998-09-14
981987
Three currently available hydromechanical transmissions have been considered, all targeted at the off-highway market. For the purposes of this paper, these are designated Types “A”, “B” and “C”. Each unit has discreet qualities and types of application, and further differences will be highlighted. To provide a reference, a conventional six speed power-shift transmission has also been included, with a down-stream range change unit, held in “Hi” range; designated type “X”. The problem Ricardo have addressed in this paper is how to compare and contrast the qualities of these units for a potential user, who may not be familiar with off-high-way applications. The example considered in this study is a mobile rough-terrain crane manufacturer, contemplating a 25 tonne machine with a 193 kW engine and an on-highway max. speed of 75 kph.
