压电喷射点胶阀的喷射性能分析及实验研究

Analysis and Research on Jetting Ability of the Jet Dispensing Valve Driven by a Piezostack

利用压电叠堆具有较好的响应特性和输出特性的特点,提出了一种新型压电驱动式喷射点胶阀。该喷射点胶阀主要由压电叠堆、杠杆式微位移放大机构、阀杆和喷嘴组成。对胶液实现喷射的条件进行了理论分析,并利用ANSYS软件对喷嘴重胶液流场进行仿真,得到了阀杆位移、胶液黏度和驱动气压对喷射点胶的影响规律,最后通过实验验证了理论分析和仿真的正确性。当胶液的黏度为2 Pa.s时,获得的胶点最小直径为0.5 mm,胶点一致性误差在6%以内。为电子封装业提供了更加高效和准确的点胶方法。

A new kind of jetting valve driven by the piezo-stack using its quick response and good output properties was presented.The jetting valve was comprised of piezo-stack,flexible lever beam,needle and nozzle.The force of adhesive when jetting was analyzed.Using ANSYS software the adhesive field at the nozzle was analyzed and simulated,getting the jetting regularity affected by the needle displacement,the driving air pressure and adhesive viscosity.Then the property of the jetting valve was tested in experiment,which verified the theoretical analysis and the simulation in ANSYS software.When the adhesive viscosity is 2 Pa·s,droplets of minimum diameter 0.5 mm could be obtained from the jetting valve and conformity error is about 6%.The jetting valve provides more efficient and precise method for the electronic packaging.