Elastic Collision Theory In The Calculation Of The Impact And The Impact Of Dynamic Stress Applied Research, Engagement Gear Line

As a result of deformation of gear tooth under load and machining error, gear meshes outside the normal path of contacting line in the gear tooth meshing start location, and gives birth to meshing-in impact and meshing-out impact, also intitules corner contact impact. The research shows corner contact impact is one of the main reason for resulting in vibration,noises and spot corrosion wreck of gear transmission.The paper uses gear teeth of a spur gear as analyzing object, and uses elastic collision theory to study gear meshing impact problem on ANSYS/LS-DYNA of explicit dynamic software which mostly included meshing impact force and impact dynamic stress.About meshing impact force, the mathematical model of the gear meshing impact and collision are presented. The gear meshing-in impact process was simulated. For the first time using FEM software to get impact force numerical value. The relationship between the impact velocity and the impact force, and that between the gear breadth and the impact force are given. The accurate impact time is obtained.About impact dynamic stress, for the first time using wave-motion theory to study impact dynamic stress. We can see clear spread image of stress-wave using ANSYS/LS-DYNA. By studying the influence of impact velocity on impat force, actually bigger dynamic stress mainly concentrates on contacting areas and near the root of teeth; traditional calculating formula of tooth surface contact stress and root of tooth bending stress don't consider corner meshing impact which is typical work condition, so two formulas need correction; at lower rotation speed, the dynamic stress value calculated by method of wave theory is lower, so it can't bring gear breakage,but at higher rotation speed, stress is bigger than the one at lower speed, and bigger rotation speed causes bigger stress. When rotation speed reaches certain limits, the dynamic stress calculated by using wave theories has even greatly exceeded stress limit, this indicates that gear designing adopting conventonal design way is unreliable in high speed transmission.The work suggests elastic collision theory can be very good applied to study of gear corner contact impact. a new approach for studying gear meshing impact, and shows the usefulness of ANSYS/LS-DYNA for solving the gear corner contact shock problem outside the normal path of actiont line.