An innovative quasi-continuous power transmission system

Conventional stepped power transmission systems exhibit abundant energy dissipation, complicated handling and costly maintenance. On the other hand, continuously-variable power transmissions (CVTs), which are recently considered to be used in the industry, despite their high capabilities, face a number of drawbacks including limited torque transmission capacity, high-precision manufacturing and installation requirements, low cost effectiveness and relatively modest power transmission efficiencies. Therefore, innovative power transmission systems that intend to resolve or lessen one or more of these disadvantages are critical in power transmission from pinion to wheel in electric traction motors of both diesel and electric locomotives; especially when active and advanced control of traction effort and adhesion is of high importance and are going to be welcomed by rail industries. In this research, an innovative quasi-continuous power transmission (QCPT) system is introduced. In this system, a fully-automatic gear box including six pairs of engaging gears is considered where only one pair of gears is engaged in any operating moment. The main components of the QCPT are the input and output shafts each having six engaging gears, speed regulating sensor, electrical module and intelligent pins. The governing parameter in this design is output shaft rotating speed or output torque of the system. When high output torque is needed, the system automatically transfers power to lower gears, and in the need of high output speed, higher gears are assigned. The proposed system is simple and cost-effective, while having high reliability and efficiency.