Research On Design Methods And Nonlinear Characteristics Of The Integrated Controllable Overrunning Clutch System

With the increase of the structure complexity and the demands for desired performances of the automatic transmission, Controllable Overrunning Clutch (COC) has become one of the most effective devices to simplify the structure and solve problems of shift impact and interrupt. However, restrained by the defects of the structure, most of the existing COCs could not achieve on-off control independently. Hence, it is urgent to develop more new types of COCs for vehicles. Additionally, so as to evaluate the interactions among the key components in automatic transmission and form the dynamic design criterion, it is necessary to study the nonlinear features of the Clutch-Gear Transmission System (CGTS). Therefore, a new type of COC and the closed related gear system are made as the main objects in this dissertation. From the two aspects of the design approach and nonlinear features of CGTS, a novel design method for the new type of COC, an analytical algorithm for multi gap-type CGTS, the nonlinear features of two basic CGTSs, and the experimental method for this type of integrated system are studied.The difference between the frictional clutch and COC, the difference and design difficulty among the COCs are analysed. According to the key feature of "whether the driven part could be thoroughly separated from the driving and control part", a new classification of COC is proposed, namely "Controllable Separable Overrunning Clutch (CSOC)" and "Controllable Non-separable Overrunning Clutch (CNOC)". According to this classification, a novel design approach for CSOC is proposed. And based on this new approach, a roller-type CSOC is designed and studied.The dynamic model of the newly-designed CSOC considering dynamic factors is established. Simulation of the model has revealed the selected dynamic wedge angle can keep the system stable operation. Besides, it has also been demonstrated that the dynamic indexes can meet the conventional design requirements, and the "Driving-ring mode" is more beneficial to the clutch life. And this mode is chosen to be the manufacturing scheme. The control stratege on Control-Ring and Wedge-Ring is proved to be necessary to achieve controllable separable function.To analyze the nonlinear features of CGTS with analytic Harmonic Balance Method (HBM), the describing function of the nonlinear function for overrunning clutch is derived by applying Galerkin Process. Meanwhile, in order to acquire the appropriate high-dimensional iterative initial values of the nonlinear algebraic equations in the harmonic balance calculation process, a novel Broyden-Grid Iterative Algorithm (BGIA) based on "Grid Partition" is proposed. The nonlinear dynamics models of two basic CGTSs which constitute the automatic transmission under steady state are independently derived. The amplitude-frequency characteristic curves which describe the system nonlinear features are obtained by BGIA, and related information about system stability are determined by Floquet theory.To assess the influences of configuration, structure and parameter on system performances for the two basic CGTS, the performance evaluated indexes are provided. The bifurcation structures and the routes to chaos with respect to exciting frequency for these systems are analyzed, and transformation courses of system attractors are described by bifurcation diagram, etc. The influencing laws of configuration, structure and parameter on system performance indexes are systematically summarized, and the dynamic design criteria for these systems are obtained.To validate the performances and functions of the proposed CSOC, and carry out Hardware-In-the-Loop (HIL) simulation of CGTS in the future, a real-time simulation CGTS test-bed based on the proposed novel structure "multi-RTWT (Real-Time Windows Target) mode" is designed and developed. Experiment results has shown that the proposed clutch are capable to fulfill the design requirements. When the Control-Ring and the Wedge-Ring are manipulated jointly, the Driven-Ring could be completely separated from the Driving-Ring and the Control-Ring. Hence, the control strategy are proved to be valid and reliable, and the proposed design approach can also be verified.