Research On Static And Dynamic Characteristics Of The Chain Transmission System For Heavy Duty Apron Feeder

Apron feeder, which is driven by the chain transmission system, is one of the core components of mobile crushing station. The chain transmission system plays an important part in the work performance and safety of apron feeder. To bear the considerable weight and impact load from the materials, the apron feeder has quite a strong vibration during work, also the chain and sprocket wears easily. It has become an urgent issue for self-design of mobile crushing station on how to evaluate the impact load from the material on the feeder, to study the source of vibration, and to explore the dynamic characteristics of chain transmission system.Aiming at the vibration problem of apron feeder, this paper equivalents the chain transmission system to a five bar mechanism according to the basic structure features of conveyor chain, and derives a formula of velocity fluctuation for the chain which indicates the number of teeth and pitch have the most influential effect on the vibration. The model provides a theoretical basis for the dynamic simulation in the subsequent chapters.The force distribution of the chain is analyzed in this paper according to the actual working condition which includes stable and impact load situations, it shows the impact load causes a significant increment of chain force. A mechanics model of the meshing area is proposed with the elongation of the chain link, tooth profile clearance and initial pressure angle. Forces between chain link and sprocket are calculated, and the influence of these factors on force distribution of the sprocket is studied, it reveals the force direction and value in the meshing area are changed when the fiction angle and the elongation are considered.The correctness of the velocity vibration formula of the chain is proved by the multi flexible body dynamics technique, and the dynamic response of the chain transmission system, stress and strain of roller and pin are solved through simulation. The similarities and differences of the force distribution in the meshing area are analyzed between theoretical, rigid and flexible model, and it provides a theoretical reference for the design of chain transmission system of apron feeder.