The Synthesis Method of Electro-Hydraulic Schemes of Mechatronic Control Systems for Hydromechanical Transmissions

The multispeed hydromechanical transmissions (HMT) belong to the most complicated automotive components. For many years the theory and the methods of the HMT analysis and synthesis were developed. For example, the “Lever Analogy” method is known (see SAE Pub. N810102 (1981). New computer-aided methods allow synthesis HMT kinematic schemes with preset gear ratio ranges.

The most important element of any modern HMT is the mechatronic control system (MCS), that practically gives to it the properties of continuously variable transmission. The base of MCS is the electro-hydraulic part, that defines its liveness and safety. Nevertheless, the analysis shows that apparently there are no generally accepted methods of their construction.

In this paper the analytical method of synthesising HMT electro-hydraulic control system is proposed. It is based on the theory of analysis and synthesis of discrete logical devices which is well known in technical cybernetics.