Automatic Transmissions: Technology “Clutch-to-Clutch Shifts” — History and Current Status

Abstract

The current state of technology of control of transient processes in automatic transmissions (AT) and integrated power units with AT by means of coordinated control of slipping clutches without a power flow gap is considered. The stages of development, revealing the logic of improving technology in general, its main differences from the previous ones are presented. The main components (phases of the transient process of the switching of the AT stages, identification of the moment of the stoppage of the friction piston, the characteristics of the algorithms complexes, the principles of precision control, etc.) are considered. Based on the analysis of a large volume of foreign publications, the results obtained by the world leading manufacturers of ATs in this direction are summarized. In the Russian language they are mainly published for the first time and are considered in the paper as the established new basic control technology for AT – “CTC technology” (originally – “Clutch-to-Clutch Shifts” technology).

Keywords

• mobile cars
• automatic transmissions
• mechatronic control systems
• switching technology of “clutch-to-clutch shifts” stages