为了获得与微米级零件尺寸相匹配的pL级胶滴, 分析了注射式、喷射式和转移式3种常用的微小液滴生成机制。基于注射式原理设计了一种时间压力型pL级点胶方案, 通过视觉在线检测胶斑直径, 控制点胶针尖内径、作用压力和时间, 得到pL级胶斑。实验研究了针尖内径、压力、时间对胶斑直径的影响, 并将此方法应用于激光惯性约束核聚变实验中冷冻靶装配时靶丸零件与充气管零件之间的微胶接。实验结果表明：胶斑直径与点胶针尖内径、压力和时间三者成正比例关系, 当使用端部1.2 μm内径的点胶针, 设置压力为0 psi(1 psi≈6.895 kPa), 时间为8~10 s时, 可以满足胶斑体积小于3 pL, 直径小于40 μm的指标要求。该方法可实现微米级零件微胶接时的pL级点胶, 而且工艺简单, 易于实现。

To obtain pL class adhesive drop to match the micro parts in size, three kinds of micro drop making mechanisms, injection, bubble jetting, and needle transfer,were analyzed. A pL class adhesive dispensing approach based on time-pressure dispensing was present,then pL class adhesive spots were obtained by online visual monitoring of the spot diameter, and controlling the internal diameter of the dispensing needle tip, pressure and time. The effects of three factors mentioned above on the adhesive spot size were experimented, and this technique combined with a micromanipulation system were used in Inertial Confinement Fosion(ICF) experiments to bond a fill tube and a capsule together for the cryogenic targets. The results show that the adhesive spot diameter is proportional to the internal diameter of the dispensing needle tip, pressure and time. When the internal diameter of needle tip,pressure and time are controlled to be 1.2 μm, 0 psi, and 8~10 s,the adhesive volume and diameter will be less than 3pL and 40 μm, respectively.