Electronically Controlled Semi-Automatic Transmissions for Heavy-Duty Trucks

The driver of a heavy-duty vehicle with unsynchronized manual transmission has been required to make several precise movements in order to make a ratio change. Driver error during shifting, due to inexperience or carelessness, can cause damage to the transmission which increases maintenance cost. To overcome these problems in an efficient and economical manner, a system of controls has been added to a basic mechanical transmission which will complete the shift at the command of the driver. Electronic logic is used as a controlling media over an electropneumatic shifting system and an electromechanical synchronizing system. The various new components of the system and how they interreact will be presented.