Research On Dynamics Of High Speed Box Opening Machine For Medicine Packaging Line

The opener is a typical packaging machine in light industrial machinery,which is composed of a linkage mechanism,a cam mechanism,a gear mechanism and a pulley mechanism.Based on SolidWorks,the 3D solid model of the mechanism was established.Based on it,the pure rigid body model and the rigid-flexible coupling model of the opener were established by using ADAMS and ANSYS.Based on the dynamic analysis of the mechanism,the rigid-flexible coupling model can better reflect the actual motion state of the mechanism and can analyze the force of key components.It is found that the rocker 2 is the most stressed member.When the rotational speed exceeds 340r/min,the stress will exceed the ultimate stress of the material of the rocker 2,thereby causing damage to the component,and the rotational speed is the limit rotational speed of the mechanism.When the rotation speed exceeds 600r/min,the opening angle of the mechanism is larger than the ideal angle due to the elastic deformation of the rod,so that the motion output of the mechanism is not accurate.The cam mechanism is the core of the opener.Based on the two models,the cam mechanism is analyzed.The conclusions have guiding significance for the initial assembly of the opener.It is proposed that increasing the damping and reducing the thickness of the cam can effectively improve the dynamic performance of the mechanism.The modal analysis of the cam after changing the thickness is carried out to verify that resonance does not occur.The cam curve is the core of the cam mechanism.Based on the ADAMS,the reverse curve principle is used to design the cam curve,and the cam curve in the original mechanism is identified as a cosine curve.The non-stop correction constant velocity curve and the no-stop correction trapezoidal curve are designed.The former is suitable for emergency parking requirements,and the latter can comprehensively improve the dynamic performance of the mechanism.Based on the no-stop correction trapezoidal curve,the cam motion angle and the maximum swing angle of the cam link are redistributed,which can further improve the dynamic characteristics of the mechanism.Through the comprehensive dynamic analysis and improvement of the opener,the theoretical basis for the safe and reliable operation of the opener is better laid.