超声振动减小脱模阻力的研究

Investigation on Reducing Demolding Force by Ultrasonic Vibration

以方形壳体塑件为对象,设计了超声振动辅助脱模成型模具,分析了塑件脱模阻力的特点及振动系统的谐响应特性,进而研究了超声振动对塑件脱模阻力的影响。有限元计算及理论分析结果表明振子谐振时超声能量能够促使其产生非线性的体积收缩和扩张变形振动,帮助塑件克服脱模初始时刻所受的粘着力,改善摩擦接触表面工作状态,减小型芯对塑件的摩擦力,从而降低脱模阻力,为解决塑件脱模困难的问题提供了新的方法。

The present work chose the rectangular injection shell as research object, designedan ultrasonic vibration assisting demolding injection mold, analyzed the characteristics of theejection resistance and the harmonic response of ultrasonic vibration system, and then studiedthe influence of ultrasonic vibration on the ejection resistance. The results indicate thatultrasonic energy could induce the nonlinear vibration of ultrasonic oscillator with volumetricshrinkage and expansion in a state of resonance, to help plastic part overcome the adhesive forceof core at the initial moment of demolding process, improve the work condition of friction pairs,and reduce sliding friction between plastic shell and core, so that the demolding force could bereduced and a innovative method to solve the demoulding problem of injection moulding hasbeen provided.