| A multi-pinion parallel transmission system that has several small gears to drive alarge gear and form a power split, is a multi-point meshing mechanical systems, especiallyfor applications with high torque, low speed. This transmission is widely used in the formof the rotation system of shield tunneling machine. Although this type of redundant paralleldrive mode can provide a huge driving force, but the existence of inevitable manufactureand installation errors, and different installation arrangement of the drive motor will makethe parallel branch of system to deliver uneven loads, resulting in unbalanced load of thedrive motor, the serious unbalanced load can cause production accidents occur. Therefore,it is necessary to study the load transfer characteristics of system and analyze how thedifferent layout form of driving motor to influence load-sharing characteristic of systems,providing reference for engineering practice.In this paper, the force transmission of multiple gear rotation system has beenconducted experimentally. The finite element model of multi parallel gear drive system isestablished, and the modal analysis of system and analysis of load transfer of statics anddynamics is done. The correlation between different layout form of three driving motorsand load-sharing characteristic of system is investigated. Finally this paper establish alumped parameter model of system, defines load-sharing coefficient of parallel gears drivesystem, using Matlab/Simulink for dynamic simulation and analyzing how contact ratio，supporter stiffness and installation layout form of the pinions to influence load-sharingcharacteristic of systems. The result shows that the larger contact ratio and support stiffnessof pinion is，the better load-sharing characteristic of systems is; Load-sharing characteristicof systems is good in both type of270°-180°-60°and180°-60°-0°, load-sharingcharacteristic of systems is poor in both type of270°-180°-0°and270°-60°-0°.Firstly, it is targeted at Rotary system with more gear parallel driven of experimentalplatform of simulation shield machine, through experimental platform of Stewart loadloader to impose three species of condition of no-load, torque and bending-torsionalcoupling, through control software to achieve two species control way of the driven motor with active control and synchronization control, through transforming installed location ofthe driven motor to achieved four species installed layout forms, analysis and research forcharacteristics of force transmission of the driven motor at different working condition,and different control forms and different installed location.Secondly, the finite element analysis model of rotary system by FEM softwareABAQUS is established. The correlation between the inherent characteristic of system andthe load-sharing characteristic of systems is studied by modal analysis. By analyzing twodifferent conditions of torsion and bending-torsional coupling, this paper studies the forcetransfer characteristic of the pinions at variation load conditions and four kinds of differentinstalled location，and the equivalent model of gear surface of the parallel gear drivesystem is established.Finally, based on the Newton-Euler theorem, and the result of modeling of meshingstiffness，the system dynamics model for single-gear drive with the support stiffness,bearing damping, gear mesh stiffness, and meshing damping is established. Then, themodel extended to multiple gear transmission system. The load-sharing coefficient ofparallel gears drive system is defined. By using Matlab/Simulink for dynamic simulationthe correlation between contact ratio，supporter stiffness, installation layout form of thepinion and load-sharing characteristic of systems is studied. The load-sharing characteristicof different installation arrangement of gear transmission system are evaluated. |
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