Innovation Design And Investigations On Movable Tooth Indexing Cam Mechanism

The indexing cam mechanisms, which is conventional in auto-mechanical equipments, is widely used in sorts of printing and packing machines because of its advantages of high speed and indexing accuracy. With the high speed development of auto machine, however, existing indexing cam mechanisms can't meet the requirements of higher indexing speed any more. Thus, a kind of new high speed indexing mechanism is researched.From the movable tooth transmission, a new high speed indexing transmission mode is designed, with characteristics such as compact structure, I/O co-axis and co-speed, any index achievement, continuous engagement and self-lock in reverse stroke.Two new indexing mechanisms are proposed: the eccentric mechanism and the pinion and rack mechanism, and focusing on the eccentric structure, the transmission principle are expatiated, mechanism design and structure parameters are also defined. The equations of the cam's contour are derived based on meshing theory of conjugating surfaces, meanwhile, geometric properties are analyzed. kinematical effects are mainly researched, and parameters selection principle is proposed.Kinematic analysis is researched methodically, with the three-dimensional modeling and the motion simulation using Pro/E software, the feasibility of new mechanism motion and the reasonableness of the structure design are verified. Dynamic static force analysis is completed, inertia force balance can be achieved because of the symmetric placement of the parts.Considering equivalent contact stiffness and torsion stiffness of I/O axis, multi-degree of freedom electrodynamics'modeling is established. A kinematics equation is solved based on variable step-size Fourth-order Runge- Kutta method. A prototype is designed and verifies the validity of the kinematical modeling. Finally, theory basis is built for the dynamic design of this mechanism.